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ddewhurst
08-23-2004, 09:41 PM
On the spec line for a limited prep Production car the spec line states:

"Cylinder head prep per IT specifications except that head may be milled to achieve max compression ratio (I.e. no porting, stock valve job, no chamber mods)."

What is your understanding of "Cylinder head prep per IT specifications" ?

What is your understanding of "Stock valve job" ?

Thanks http://Forum.ImprovedTouring.com/it/wink.gif
David

Geo
08-23-2004, 11:17 PM
Originally posted by ddewhurst:
What is your understanding of "Cylinder head prep per IT specifications" ?

Port matching, stock valve job, mill to meet CR.


Originally posted by ddewhurst:
What is your understanding of "Stock valve job" ?

As called out in the FSM. Many (if not most) FSMs call out the specific angles for a valve job, usually with some tolerance.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

Bill Miller
08-24-2004, 06:41 AM
David,

What GEorge said is pretty much it. If the FSM calls for a 3-angle valve job, that's what you get. If it calls for a 2-angle, that's what you get. My VW FSM (Bentley) has very detailed diagrams, w/ the angles, and the length of the surface covered by those angles.

As far as porting, you're allowed a 1" port match on the intake and exhaust side.

I'm curious as to why you're asking this. Are you getting rid of the Mazda?

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

ddewhurst
08-24-2004, 09:11 AM
Geo & Bill, thanks for the info. http://Forum.ImprovedTouring.com/it/smile.gif

Second part of the question which comes from a conversation with a fellow racer. When the Production car "Lmited Prep" spec line has no mention or specification of the cylinder head valves does one then fall back to the PCS spec for valves? D.1.f.4 "Any metal valves meeting the specified head diameter may be used."

***Are you getting rid of the Mazda?***

Bill, shame on you for talking this way. The Mazda & my economic path run parallel. I have only raced onced this year. Kind of hit a wall or needed a stress free summer. Will you be at the Runoffs ? If so I'll see you at the Bergs deal. Do you have any idea how much a paddock on the asphalt costs?

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

racer_tim
08-24-2004, 11:07 AM
David, the valves have to be the stock diameter, just like in IT. You can use different valve springs, but other stuff must be ferrous.



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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

Greg Gauper
08-24-2004, 11:40 AM
The other difference is that in IT you can only remove enough material from the head to either reach a 0.5 increase in compression, not to exceed 0.025".

In LP Prod you can take as much off the head as you like as long as you do not exceed the spec line limit of compression for your motor. However that isn't the best way to make power....since pistons are free in LP, the preferred method is to keep the head as close to stock as possible and go with domed pistons to get to your CR limit.

The only area I have ever questioned is the 3-angle valve job (I happen to run the stock Honda configuration).....My shop manual does provide a very detailed description and diagram of the 3-angle valve job. I have been told that any dimension is an absolute minimum (i.e. weight) or an absolute maximum (i.e. track, valve diameter, bore & stroke, etc). So what happens in a 3-angle valve job? Do I use a minimum limit or a maximum for each 'angle' of the valve job? Am I non-compliant if I maximize the 1st & 3rd angle and/or section width, but minimize the 2nd angle and/or section width?

ddewhurst
08-24-2004, 07:41 PM
Tim, I do appreciate your responses. Back to my second post question. In the PCS spec line for IT cylinder prep if the cylinder head prep spec is for prep of the cast block & nothing on the spec line refers to the valves dose one go back to the PCS rule D.1.a.4 for the valves. "Any metal valves meeting the specified head diameter may be used." If that is a true statement what is the back-up to make it a true statement ?

Greg, on what page are the min/max dimension measurement rules taht you speak of ?

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

ps: It's fun to learn on this site without someone ripping the family THINGS out.

racer_tim
08-24-2004, 09:36 PM
David, that's a good point. I'd stay with the the old line" If it doesn't say you can, then you can't". That is for IT as well as production.

I've been told that if I go with the 7mm VW valves instead of the 8mm ones, that I would be illegal. The smaller diameter would flow better, but how much bang for the buck are we actually talking about, with a LP VW head, with 40mm intake and 33mm exhaust valves, .420" lift cam, and 1" IT port/polish.

I don't think the cost of these valves and guides would be worth it.

Just my $0.02 worth



------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

Greg Gauper
08-24-2004, 10:41 PM
GCR Page 96
Section 11.4 Measurement Standards

racer14itc
08-24-2004, 11:15 PM
Originally posted by racer_tim:
David, that's a good point. I'd stay with the the old line" If it doesn't say you can, then you can't". That is for IT as well as production.

I've been told that if I go with the 7mm VW valves instead of the 8mm ones, that I would be illegal. The smaller diameter would flow better, but how much bang for the buck are we actually talking about, with a LP VW head, with 40mm intake and 33mm exhaust valves, .420" lift cam, and 1" IT port/polish.

I don't think the cost of these valves and guides would be worth it.

Just my $0.02 worth



Yes, but if you go with the 8mm guides and valves with turned down stems, that IS legal since valves are "free" in the prod rules. You'll get the same benefit as smaller valve stems and guides.

MC


------------------
Mark Coffin
#14 GP BSI Racing/Airborn Coatings/The Shop VW
Scirocco
Zephyr Race Coaching and Consulting
http://pages.prodigy.net/Scirocco14gp

Bill Miller
08-25-2004, 06:50 AM
Originally posted by racer14itc:
Yes, but if you go with the 8mm guides and valves with turned down stems, that IS legal since valves are "free" in the prod rules. You'll get the same benefit as smaller valve stems and guides.

MC





Mark,

With all due respect, I have to disagree. While valves may be free in Prod, the l-p cars say IT prep on the head. The way I read that, is IT prep as it relates to valves. The mod you mention is not legal in IT, so I can't see it being legal on a l-p Prod VW (or any other car).


------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

ddewhurst
08-25-2004, 08:46 AM
When the spec line for a LP car states:

"Cylinder head prep to IT specifications except that the head may be milled to achieve max. compression ratio(I.e.no porting, stock valve job, no chamber mods)."

The rule dose not spec Cylinder head assemble or complete cylinder head.

I understand this spec line information to mean "bare cast head prep" (the rule written words reference is to machining/preparing the bare cast head) per rule ITCS D.1.l. this rule states nothing about valves. I find no other written spec for the IT "cast head prep".

Is this understanding of the rule correct ?

If this understanding of the rule is correct dose one then go to the PCS valve rule ? Any valve meeting the specified (stock) head diameter may be used with the FSM grind.

Have Fiun http://Forum.ImprovedTouring.com/it/wink.gif
David

racer14itc
08-25-2004, 11:05 AM
Originally posted by Bill Miller:

Mark,

With all due respect, I have to disagree. While valves may be free in Prod, the l-p cars say IT prep on the head. The way I read that, is IT prep as it relates to valves. The mod you mention is not legal in IT, so I can't see it being legal on a l-p Prod VW (or any other car).




Just my interpretation of course. In the ITCS, the rules do NOT have a separate clause allowing any valve w/ same head diameter, but the PCS does. If I were building a limited prep car (and I'm contemplating it) I would have no problem using valves of a different design than stock.

Rick Haynes recently said it best when he said, and I'm paraphrasing here, "some folks read the rules disadvantageously to themselves. That's why some folks win and some folks lose." My own personal philosophy is that if I can point to a rule or clause in the rules that permits me to do something, then I feel comfortable in doing it. If it's a loophole that the rulesmakers never intended, then it will be closed and I'll have to deal with it then. E.g. the thermal barrier ("plating or painting") rule in IT.

MC

------------------
Mark Coffin
#14 GP BSI Racing/Airborn Coatings/The Shop VW
Scirocco
Zephyr Race Coaching and Consulting
http://pages.prodigy.net/Scirocco14gp

ITSRX7
08-25-2004, 11:55 AM
Let me get this straight. The Production rules say that you can use any valve. The Limited Prep rules say that you must use the IT-prep head rules.

I just don't see how you can make the argument that valve size is free within the confines of IT head prep.

What consitutes the head? The whole, fully assembled unit. The ITCS doesn't seperate each into it's own section.

The ITCS rules with regard to head prep are located at ITCS - page 11 D.1.L and ITCS page 12, D.1.P.

Guess what the latter says? "All engine components not otherwise listed in these rules shall meet specifications for stock parts. Where factory specification are absent or unclear, e.g., cylinder head thickness and/or combustion chamber deapth, etc., the Club may establish an acceptable dimention and/or allowable tolerance..."

You can't cherry pick from both rule sets unless I am missing something specific.

AB

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Andy Bettencourt
ITS RX-7 & Spec Miata 1.6 (ITA project)
New England Region R188967
www.flatout-motorsports.com (http://www.flatout-motorsports.com)

ddewhurst
08-25-2004, 12:43 PM
Andy, Mark, Bill, following is the specification from a LP spec line in the PCS.

"Cylinder head prep to IT specifications except that the head may be milled to achieve max. compression ratio(I.e.no porting, stock valve job, no chamber mods)."

The rule dose not spec Cylinder head assemble or complete cylinder head.

I understand this spec line information to mean "bare cast head prep" (the rule written words reference is to machining/preparing the bare cast head) per rule ITCS D.1.l. this rule states nothing about valves. I find no other written spec for the IT "cast head prep".

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

Greg Gauper
08-25-2004, 12:56 PM
Andy,

By that logic, and OHC car could not legally install a different cam with alternate lift & duration, since the cam is installed in the head, but a pushrod motor could since the cam is in the block.....

I'm with Mark & David on this one, in that the head prep is refering to a bare head assembly. Valves are 'free' in Prod, but the size is still specified in the PCS.

[This message has been edited by Greg Gauper (edited August 25, 2004).]

racer_tim
08-25-2004, 05:16 PM
Greg, look @ PCS page 9, paragraph e.1. It pretty much defines what the "cylinder head" is and paragraph f. defines what the camshaft is.



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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

Greg Gauper
08-25-2004, 07:44 PM
Tim,

Yes I know it is defined (it's actually page 10, not page 9). I was trying to make a point about Andy's argument which (I am assuming) he interpetted to mean that since the valves are part of the head and the head is to be prepped to IT rules that you have to run stock valves in spite of the fact that D.1.f.4 (page 11) states any valve may be used. I was merely stating that by Andy's reasoning, you couldn't change the cam in an OHC motor either because it's part of the head assembly and IT prep rules don't specifically permit an alternate cam. I myself do not agree with this interpretation.

And I still stand by the interpretation that the cylinder head prep rules as they pertain to limited prep production cars refers to the bare cast head prep. Further, it states any valves meeting the specified head diameter may be used, any valve springs, any valve guides, and any cam (meeting the LP specs for maximum lift), so Mark's idea is legal.

[This message has been edited by Greg Gauper (edited August 25, 2004).]

racer_tim
08-26-2004, 12:16 AM
Mark and Greg, maybe this discussion needs to be on the prod site instead of the IT site.

Mark, I have heartburn with stating that valves are "free" in Limited Prep, that you can "turn down the stems". I don't think that this goes with the intent of the Limited Prep head prep per "IT" specs.

Yes, the head is different than the valves, but which rule takes priority?

I take "IT head prep" to mean that you can't do more to the valves than a stock valve job.

Tim

lateapex911
08-26-2004, 03:26 AM
Great thread guys! Keep going.

Right now I am leaning towards the logic of the valves not falling under the IT head prep rules as the cam example sets a precedence.

But.....at first I assumed the opposite. Great out of the box thinking.

I am though unfamiliar wiht Prod rules Is it fair to say that a prod car can run non stock valve sizes that are listed on the spec line, and a cam that is non stock but meets specs and so on?

If so, the LP rules appear to limit valve size to stock, while allowing other specified changes.

I suspect this is a letter of the rule legal mod.

------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

Bill Miller
08-26-2004, 07:01 AM
Mark,

I understand your logic (along w/ David's and Greg's), and you guys may be correct. And you're right, you have to read the rules to your advantage.

Greg,

The fault that I find w/ your cam arguement, is that the cam specs are listed on the vehicle spec line.

Since this is the 'official IT / l-p Prod' thread, here's another one to chew on. For example, the spec line of most of the l-p cars says "factory spec at all 4 wheels" for brakes. Yet the PCS says that all cars can convert to rear disc brakes. So, does that mean that an l-p car (e.g. Rabbit) that came w/ drums can convert to discs???

Discuss!

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

ddewhurst
08-26-2004, 09:03 AM
Bill, with respect to your rear brake drum/disc post it's my understanding that the spec line over rides the PCS written words.

Tim, I posted the original subject on the IT site with hopes that open minded thinking that is occuring would continue.

Please continue http://Forum.ImprovedTouring.com/it/wink.gif
David

Greg Gauper
08-26-2004, 09:27 AM
Bill,

Yes I understand that the cam specs are listed on the vehicle spec line. The general GCR rule also states that 'any' cam may be used. It also states that any valve may be used. In one of the above response, somebody argued that you couldn't use alternate valves because then the head would no longer be prepped to IT specs, even though the PCS says you can use any valve. I was just using the cam example to refute that argument.

Regarding the brake issue, my understanding is that of David's, in that the spec line overrides the PCS, so if it says 'Factory Spec at all four wheels' you can't convert to rear discs, but if it doesn't say that, you can (come to think of it, that is a bit awkward, normally the rule of thumb is "if it doesn't say you can, then you can't" but here it's kinda sorta backwards, kinda like the reverse Polish notation when working with one of them there HP calculators

And I do feel that this is an acceptable discussion for this website since many IT drivers do convert to LP prod and several of us former IT drivers (Myself, Tim, Mark) have gone this route and are willing to share their advice.

[This message has been edited by Greg Gauper (edited August 26, 2004).]

Bill Miller
08-26-2004, 05:57 PM
Greg and David,

I'll tell you, my thinking in regards to the brakes was exactly what yours is. However, when I was at the Pocono dbl National this past weekend (also know as the Pa. monsoon!), I was speaking w/ a competitor about his l-p HP car, and I was commenting about the rear disc brakes, w/ the Wilwood calipers. I asked the same 'factory spec' question. He gave me his logic, that there are many full prep cars in the PCS that have no alternate brakes listed, yet they're allowed to convert to rear discs. Also, there's nothing in the Restricted Suspension section (really, the meat of l-p), that says anything about the brakes being limited to stock configuration.

Now normally, I would have said, "that's a pretty creative interpreataion, but I'm not sure it would pass tech", to which he promptly responded that it made it through tech at the '03 Runoffs. That kind of sheds a whole new light on things.

Discuss

As far as the valve issue, I'd be real curious as to what the official position is, and would be willing to chip in to help pay for a clarification. I bet we could get 10 or 20 guys to go in on it. I'll also speak to a friend of mine who's on the PAC, and who drives an l-p car.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

racer14itc
08-26-2004, 07:05 PM
Originally posted by Bill Miller:
Greg and David,

I'll tell you, my thinking in regards to the brakes was exactly what yours is. However, when I was at the Pocono dbl National this past weekend (also know as the Pa. monsoon!), I was speaking w/ a competitor about his l-p HP car, and I was commenting about the rear disc brakes, w/ the Wilwood calipers. I asked the same 'factory spec' question. He gave me his logic, that there are many full prep cars in the PCS that have no alternate brakes listed, yet they're allowed to convert to rear discs. Also, there's nothing in the Restricted Suspension section (really, the meat of l-p), that says anything about the brakes being limited to stock configuration.

Now normally, I would have said, "that's a pretty creative interpreataion, but I'm not sure it would pass tech", to which he promptly responded that it made it through tech at the '03 Runoffs. That kind of sheds a whole new light on things.

Discuss

As far as the valve issue, I'd be real curious as to what the official position is, and would be willing to chip in to help pay for a clarification. I bet we could get 10 or 20 guys to go in on it. I'll also speak to a friend of mine who's on the PAC, and who drives an l-p car.



Making it "through tech" at the Runoffs really doesn't mean ANYTHING, since if your logbook is up to snuff, tech at the Runoffs consists of showing your driver gear and logbook.

If the Scirocco you speak of qualifies/finishes in the top 4 at the Runoffs, we'll see how far he gets with those rear disc brakes attached. I suspect not very far...and the shame of it is that it's not really worth the risk or aggravation of getting protested/DQ'd for something that isn't a performance advantage on a Scirocco. Having the rear discs isn't going to make the car an instant Runoffs contender. It's definitely a convenience factor, which is why I run rear discs on the GP car (full prep).

MC

------------------
Mark Coffin
#14 GP BSI Racing/Airborn Coatings/The Shop VW
Scirocco
Zephyr Race Coaching and Consulting
http://pages.prodigy.net/Scirocco14gp

ddewhurst
08-26-2004, 07:47 PM
Bill, I took a quick look at the spec lines for LP H cars & they all say Alternate brakes: None

I would cough up for the valve thing.

Have Fun ;
David

racer_tim
08-26-2004, 08:19 PM
OK, here is my order of which rules / specs takes precedence.

PCS Spec Line for my Vehicle
PCS Section on Limited Prep
PCS Section on Production
GCR

So, which rules/specs are listed in my particular Spec line for my vehicle is at the top of the list, no matter what else is said in the rest of the rule book.

Yes, we all read into the rules what we want to, but that's because we all want to squeeze out as much as we can from our "bang for the buck"

Disks on ANY VW A1 LP car is a no brainer. Can't be done. Unless you can show me a Bentley or Chilton manual with disks on a pre 1985 Rabbit or Scirocco. End of discussion.

Making it through "tech" is much different than making it through "impound" with a medal around your chest.



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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

Bill Miller
08-26-2004, 11:54 PM
<font face=\"Verdana, Arial\" size=\"2\">If the Scirocco you speak of</font>

Mark,

I don't believe I said anything about a Scirocco. In fact, I don't believe I mentioned what kind of car the person I spoke w/ drove.

David,

I also see cars w/ nothing listed in the alternate brake column. Does that mean they can't convert to rear discs? How is 'None' different than no entry?

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

Drew Aldred
08-27-2004, 12:22 AM
Originally posted by racer14itc:
If the Scirocco you speak of qualifies/finishes in the top 4 at the Runoffs, we'll see how far he gets with those rear disc brakes attached. I suspect not very far...

I agree that he won't get very far in impound, but he might get tripped up before then during the week. I was invited to tech after the first three sessions last year and one of the things they checked were brakes and size of brakes.

drew



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#42 GP Spitfire
Member 289368

ddewhurst
08-27-2004, 06:34 AM
Bill, the following is my understanding of the written rules for brakes. On the spec line NONE means there are no, zip, zero alternate brakes. On the spec line an entry means those would be the alternate brakes. No entry means read back through the PCS (if nothing ) read the GCR.

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

Bill Miller
08-27-2004, 06:41 AM
David,

That's certainly one way to look at it. Yet another example of how there's inconsistency in the way the GCR and various CS sections are written.

Now, in the conversation I had w/ this individual, the stated that tech looked at the brakes, and even measured the size of the discs, no issues. As I stated, my earlier belief was that this was not legal. Now, I'm just not sure.

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

OTLimit
08-27-2004, 08:35 AM
Chris laughed when I told him about the Wilwood calipers. Just because someone ran them and no one said anything doesn't mean a thing. And someone has to CARE about it before they are likely to say anything. But one of the first things they looked at on Chris' car after the race (as one of the top 6 finishers) was brakes and track. And they couldn't believe he was running drums. http://Forum.ImprovedTouring.com/it/smile.gif

And if you look at the results from Pocono, since there is only 1 VW shown for HP, it's not very difficult to figure out who you were talking about. And since he finished 7th last year at the Run Offs (but still a good finish), he did not get invited to Tech for a extra special review of his brakes and track after the most important session of the week.




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Lesley Albin
Over The Limit Racing
Blazen Golden Retrievers

Bill Miller
08-27-2004, 03:03 PM
Lesley,

I don't know where you or Mark have gotten the idea that the person I spoke with was running a VW. I have never said or inferred that it was a VW, or that it was Johannes' car. I will state now, that it was in fact NOT Johannes Kraus, or any other VW driver. This is how ugly rumors get started.

The person I spoke with said that the car in question was examined in tech, and that the brakes were measured. Once again, I am in agreement w/ the folks here, and that it's not legal. All I'm doing is relaying what I saw, and what I was told. I'm just trying to get my hands around this.

If Mark's saying that you can use any valves and guides in a l-p head, even though it says IT prep on the spec line, I'm trying to see why you wouldn't be able to do the brake swap, using the same kind of logic.

Mark,

I looked at the ITCS again, and while it says valve guide material is free, it says nothing about size being free. So while you may be able to use guides made from unobtanium, by my interpretation of the rules, it would have to be for a stock sized valve. JMHO.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

racer14itc
08-27-2004, 03:42 PM
Originally posted by Bill Miller:
Lesley,

I don't know where you or Mark have gotten the idea that the person I spoke with was running a VW. I have never said or inferred that it was a VW, or that it was Johannes' car. I will state now, that it was in fact NOT Johannes Kraus, or any other VW driver. This is how ugly rumors get started.

The person I spoke with said that the car in question was examined in tech, and that the brakes were measured. Once again, I am in agreement w/ the folks here, and that it's not legal. All I'm doing is relaying what I saw, and what I was told. I'm just trying to get my hands around this.

If Mark's saying that you can use any valves and guides in a l-p head, even though it says IT prep on the spec line, I'm trying to see why you wouldn't be able to do the brake swap, using the same kind of logic.

Mark,

I looked at the ITCS again, and while it says valve guide material is free, it says nothing about size being free. So while you may be able to use guides made from unobtanium, by my interpretation of the rules, it would have to be for a stock sized valve. JMHO.



My mistake, I inferred incorrectly from your "clue" as a limited prep HP car. You could have been more direct and just mentioned the type of car but obviously you had your reasons not to. Don't blame US for ugly rumors that get started when you make veiled statements like that.

Secondly, I'll try this again: the valves I suggested would be STOCK diameter stems where they go through the guide, w/ the stem turned down near the head. Still legal, uses stock size valve guides, w/ stock head diameter valves.

Lastly, I agree that the limited prep brake restrictions are poorly worded and wish that a clarification would be made in the PCS brake section if the rulesmakers want the limited prep cars to run factory/OEM brakes at each corner.

MC

------------------
Mark Coffin
#14 GP BSI Racing/Airborn Coatings/The Shop VW
Scirocco
Zephyr Race Coaching and Consulting
http://pages.prodigy.net/Scirocco14gp

Drew Aldred
08-27-2004, 04:15 PM
Now that Bill has told us it was not a VW, that limits the field. There were only about 6 HP cars at Pocono, it is an LP car, AND it's not a VW. Shouldn't be too hard to narrow down. I do believe some race officials read these BBs, or hear about it from others. Don't be surprised if one or all of these LPHP cars that were at Pocono get "invited" to impound during the week. Be sure to thank Bill for sharing your story.

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#42 GP Spitfire
Member 289368

Tom Donnelly
08-27-2004, 04:48 PM
Mark,

What's the difference between turning down the stem near the valve head and back-cutting a valve? Is the 'back-cut' on the head of the valve only or does it include the stem? Or is it altogether different?

Tom

hornerdon
08-27-2004, 04:57 PM
Originally posted by racer14itc:
My mistake, I inferred incorrectly from your "clue" as a limited prep HP car. You could have been more direct and just mentioned the type of car but obviously you had your reasons not to.

Had to be Plush in his 510. There were 6 HP cars at Pocono, but the only 3 that have run the Runoffs are Bartell, Kraus and Plush. Bartell is full prep, and Bill says it wasn't Krause, so that leaves Plush. My understanding is that last year, his first year at the Runoffs, his car needed a bit more development before it would attract the attention of either tech or fellow competitors.



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...Don

racer14itc
08-27-2004, 05:03 PM
Originally posted by Tom Donnelly:
Mark,

What's the difference between turning down the stem near the valve head and back-cutting a valve? Is the 'back-cut' on the head of the valve only or does it include the stem? Or is it altogether different?

Tom

Backcutting a valve refers to the underside of the head, making the transition from the valve seat surface easier. Usually one or two more angles to allow the flow to turn better. Turning the stem simply reduces the diameter of the stem from some point up on the valve stem down to the head.

Obviously neither of the things you mention is legal in IT, but with the prod rules allowing "any valve of specified head diameter" under a separate section of the PCS engine rules which applies to ALL production cars (not just limited prep) then in fact back cutting the head, turning the stem down, etc., would be legal.

Point of fact, what about valves that are longer than specified in the shop manual? If you run a smaller base circle cam, a longer valve might be necessary. Under the PCS rules it would be legal.

MC

------------------
Mark Coffin
#14 GP BSI Racing/Airborn Coatings/The Shop VW
Scirocco
Zephyr Race Coaching and Consulting
http://pages.prodigy.net/Scirocco14gp

[This message has been edited by racer14itc (edited August 27, 2004).]

Tom Donnelly
08-27-2004, 05:07 PM
Mark,

Is this what you are doing?

http://hotrod.com/techarticles/p106720_image_large.jpg

Tom

Tom Donnelly
08-27-2004, 05:11 PM
Mark,

Sorry, I posted before your answer. I'm leaving the legality discussions up to everybody else. I'm just trying to learn. The stem cut seems like it would increase flow and I found that link to hod rod magazine. IT and LP Prod seem like two slightly different worlds. I'd like to go LP/EP with my 240z.

Thanks,
Tom

racer14itc
08-27-2004, 05:29 PM
Tom,

Yep, that's a turned down stem.

Also, see how there are only two angles on the valve head? A backcut would add one or perhaps two more shallower angles where the valve seat surface meets the back of the valve. Right now there's a pretty sharp lip there, and it can disrupt the airflow. Making a couple of angles leading into the valve seat surface keeps the flow attached and increases airflow significantly.

MC

------------------
Mark Coffin
#14 GP BSI Racing/Airborn Coatings/The Shop VW
Scirocco
Zephyr Race Coaching and Consulting
http://pages.prodigy.net/Scirocco14gp

Tom Donnelly
08-27-2004, 05:35 PM
Cool. More angles smooth the curve, creating better flow. Applied calculus. So I assume you can back-cut and turn down a stem. But you would have to bench flow the setup to see if/how it improves.

Thanks again. Time to go home.

Tom

racer_tim
08-27-2004, 05:52 PM
Mark, 2 comments.

#1 You web link doesn't work.

#2 I don't think that "back cutting the head" is allowed in Limited Prep, but would be legal in Full prep. Just my $0.02 worth.

As far as reducing the diameter of the valve, between the valve and where it contacts the guide, that's in the grey area.

When we (VW's) get into the top 3 @ the run-offs, and start to get torn down, I don't think it's a problem until then.

When impound says "I want 1 intake valve, 1 exhaust valve, cam, 1 rod and piston" will questions start to be asked.

Good luck this year @ Mid-Ohio. I heard that your looking into a 1.6 motor (finally). Let me kow, I've still got all kids of 1.6 stuff in my shed.

I do agree that there are all kinds of loop-holes in the Limited Prep classifications.

------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

[This message has been edited by racer_tim (edited August 27, 2004).]

Greg Gauper
08-27-2004, 07:19 PM
It's a grey area, but I think the valves in question are legal. It depends on whether you consider the LP rules regarding IT cylinder HEAD prep as meaning the the bare, cast head, or the complete assembly. Since everything that Mark is talking about refers to the valve and not the valve seat, and since valves are in fact free as long as the base diameter is the same as stock, then it should be legal.

For that matter, I would think that a set of purchased 'Rimflow' valves would be cheaper than modifying a set of stock valves to achieve the same effect. One possible outcome of a protest would be a determination that it is a poorly written rule, and the result would stand but the rule would change/clarify the following year, similar to what Sargis went thru with the carb spacer rule.

[This message has been edited by Greg Gauper (edited August 27, 2004).]

hornerdon
08-27-2004, 08:19 PM
For what it's worth, I agree with Mark about "any valve", as long as it's (1) ferrous; and (2) has the stock head diameter. I also agree that back cutting the head and turning the stem are allowed.

Maybe this will make it more clear. Mark also mentioned cutting a couple of additional angles into the valve. That would be legal. But, cutting additional, matching angles into the valve seat would not be legal, because the valve seat is part of the head.

I think part of the difficulty in understanding this concept is because IT folks are used to thinking in terms of hull assemblies, primarily with regards to update/backdate. That same concept of a "complete assembly" really doesn't exist in Production.

Thus, in IT, a "head" includes the head casting, valves, guides, keepers, seals, springs, rockers (if any), tappets (if any), cam (if it's there), etc. But in Production, a "head" is just that -- the head casting.

You have to look at it in terms of the full prep rules. In full prep, the head can be ported, it can be milled to any compression ratio, and any valve seat angles may be used. In limited prep, the porting is limited to IT specs and the valve seats are limited to stock (as in IT). The specs specifically permit milling to achieve the compression ratio, just like in full prep.

I believe this is what they intended -- an easy way to limit the full prep specs as far as porting and valve seats are concerned. The valves, keepers, valve springs and tappets/shims are separately referenced in the specs, so they must not be part of the head.

Finally, there is this phrase in the PCS section about what you can do do a head: "On engines which are restricted to Improved Touring cylinder head preparation, the cylinder head and/or valve train may be machined for clearance to install an alternate camshaft, and adjustable cam gears are allowed." I emphasized the phrase "and/or" to point out that the PCS considers the head and the valve train to be separate items. I believe that closes the case.


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...Don

[This message has been edited by hornerdon (edited August 27, 2004).]

Bill Miller
08-28-2004, 11:33 AM
<font face=\"Verdana, Arial\" size=\"2\">Don't blame US for ugly rumors that get started when you make veiled statements like that. </font>

Mark,

How exactly was it 'veiled'? All I said was that it was an l-p HP (probably shouldn't have mentioned the class) car w/ converted brakes. Who's car it was, or what kind of car it was, were not germane to the question at hand. So, if you want to speculate as to who's car it was, or what kind of car it was, that's totally on you.

Don,

If you're back cutting the valve, you're putting more angles on it than are listed in the FSM, I'm not sure how this is legal. Also, the passage of the PCS you cite refers to maching for the purposes of installing an alternate camshaft. So, they've restricted just what type of machining that you can do. You can't justify machining on a part of the valve that has no contact whatsoever w/ the cam/tappet/lifter/etc., when it says you're only allowed to machine what is necessary to clear the alternate cam.

Mark,

You make a good case, and I guess it comes down to what the interpretation of the head is. Is it the bare casting or the whole assembly?


<font face=\"Verdana, Arial\" size=\"2\">Be sure to thank Bill for sharing your story.</font>

Kiss my ass Drew! If you, or any other driver, have a problem w/ getting called to tech to investigate a potentially illegal component, that's your problem. I mentioned something that I saw that I questioned the legality of, and decided to not be specific about the car/driver. And from what others have posted here, the majority opinion is that it's illegal. I'm not sure why you wouldn't want something like this to be out in the open. But however you feel about it, save your strong-arm comments for someone else!

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

hornerdon
08-29-2004, 04:16 PM
<font face=\"Verdana, Arial\" size=\"2\">If you're back cutting the valve, you're putting more angles on it than are listed in the FSM, I'm not sure how this is legal.</font>
Well, of course, I'm falling very strongly into the camp that in Production, the head is the casting, so the valve is not part of the head. And, the rules say "any" valve that is ferrous and has the same head diameter, so I say you can make whatever cuts you want on a valve, as long as you don't reduce the head diameter.


<font face=\"Verdana, Arial\" size=\"2\">Also, the passage of the PCS you cite refers to maching for the purposes of installing an alternate camshaft.</font>
You're correct, but that has nothing to do with the reason I cited it. I cited it because that rule clearly separates the head (casting only) from the valve train (valves, springs, keepers, tappets, lifters, rockers or what have you). If they considered the valve train to be pat of the head, they would not have had to say "and/or" in the rule; simply saying "head" would have been enough. My point is that if the head and valve train are considered separate entities in the cited rule, then they are different entities in all other rules, including what you can do to a valve.


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...Don

Bill Miller
08-29-2004, 07:07 PM
You make valid points Don. I'm still trying to understand the folks that justify the valves but not the brakes.

But this is just one more reason why the various CS sections need some major overhaul.

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

ddewhurst
08-29-2004, 07:47 PM
Bill, on the spec line under Brakes Alter.: With thE word "None" typed IMHU the word None means there are no alternate brakes. Meaning you SHALL use the brakes that came from the original manfacture. If there is nothing type under Brakes Alter.: you refer back to the PCS. If there are words typed under Brakes Alter.: that state specific brake types or sizes then you are allowed to use brakes to those written specs.

Look on page PCS-101 & you will find alL three items that I mentioned above.

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

PS: List a specific car manufacture & model & lets talk through it's brakes.

Bill Miller
08-29-2004, 09:51 PM
David,

I understand where you're comming from, but how about the case where only alternate front brakes are listed? Or where alternate rears are listed, but they are drums? Here's an example:

FP Triumph Spitfire (either Mk III or Mk IV)

Std. Brakes (F)9.0" disc ®7.0" drum
Alt. Brakes (F)9.7" disc ®8.0" drum, May use GT6 caliper as alt. front caliper

By your logic, this car would only be allowed to use either 7" or 8" rear drum brakes. Do you think Steve Sargis is running rear drum brakes? Ask Drew or his dad if they're still running rear drums (they have GP Spits, but they show the same alt. 9.7" disc and 8.0" drum).

I can see valid points on both sides of this arguement. The PCS clearly states that cars w/ rear drums may convert to discs. Nothing to differentiate a limited prep car from a full prep car, unlike the restricted suspension vs. unrestricted suspension.

To me, saying "factory spec at all 4 wheels" is no different than listing the explicit stock sizes. If anything, it saved people the time of looking up the brake sizes for all of those cars. And by the same token, leaving the alt. brake section blank is the same as saying "None". I don't necessarily see where either of those has bearing on the line that says all cars w/ rear drum brakes may convert to rear discs. Like I said, I'd be willing to chip in towards getting an official ruling on this one.

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

Knestis
08-29-2004, 10:33 PM
This is great - as a reminder why I would never go play the Production game. Eek.

K

Bill Miller
08-29-2004, 10:49 PM
C'mon Kirk, you know you want to! Get that A3 classifieed as an l-p FP car and you're on your way!!! The lure of the dark side is strong!!! http://Forum.ImprovedTouring.com/it/biggrin.gif

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

hornerdon
08-29-2004, 11:01 PM
No doubt the limited prep brake rules are open to some interpretation. I think the confusion starts because historically, all prod cars, including full prep, have been required to run factory spec at all 4 wheels with 2 exceptions: (1) if there are specific alternates listed on the spec line; and (2) they are all allowed to convert rear drums to rear discs within parameters.

So, for the limited prep cars to have "factory spec @ all 4 wheels" listed in the brake section of the spec line, the reaction could well be, "Ho hum, yeah, duh, what else is new?" But, here's the rub, and I think the controlling factor. For all Prod cars, the brake requirements are spelled out in the PCS. The alternates are in the spec line, and override the PCS. But, in addition, the limited prep cars have a specific limitation in the spec line that no full prep car has: factory spec @ all 4 wheels. Because the spec line overrides the PCS, the rear disc rule is overridden.

Follow this sequence:

* In the PCS, the brake rules are pretty well spelled out -- original calipers, alternate disc/drum material but with original sizes, rear drums can be replaced with discs, etc.

* In the Spec lines, certain cars are given specific alternates such as larger sizes for rotors/drums. This overrides the PCS.

* In the Spec lines, limited prep cars are restricted to "factory spec @ all 4 wheels". This overrides the entire brake section of the PCS.

In fact, if one wanted to question the wording of the limited prep restrictions, it would be interesting to ask, where does the brake system at each wheel stop? Does the "factory spec" include the pads? The brake lines? THAT would be an interesting protest -- slam a competitor for running a racing pad or a SS brake line!

So far, there's been pretty much a gentlemen's agreement that "factory spec" means IT level preparation on the brakes. In fact, the only limited prep car I've heard of running rear disc replacements is the report you made -- although, several people have threatened to test the rule.

Remember, it's even more limiting for the Spridgets -- some of them have to run with the tiny front drums they came with!

hornerdon
08-29-2004, 11:10 PM
Originally posted by Knestis:
This is great - as a reminder why I would never go play the Production game. Eek.

Aw, c'mon K. Unless you've been totally corrupted by the "do it this way" mindset of most educators, for a guy as smart as you the Mind Game of Prod rules is part of the fun! The rules were deliberately tilted so creative thinking is rewarded.

It goes both ways. In the case of the brake discussion, it turns out that the rules are probably more restrictive than initially apparent. But, in the case of the valves, it turns out that thinking outside of the box, and carefully comparing various parts of the rules, results in some pretty neat tricks that the average competitor may never imagine from an initial reading.

That's the very definition of Production. If you want everyone to wear dark suits and white shirts, race SRF...




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...Don

Drew Aldred
08-30-2004, 12:08 AM
Originally posted by Bill Miller:
Ask Drew or his dad if they're still running rear drums (they have GP Spits, but they show the same alt. 9.7" disc and 8.0" drum).


Yep, on both counts. Although alot of guys have gone to the disc setup with their full prep cars - I just haven't gotten around to it YET. My only point about the other issue you have with me Bill is that if you see or hear something about someone's car that's in the grey area, it may not be the best idea to post it on a public forum.





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#42 GP Spitfire
Member 289368

Bill Miller
08-30-2004, 12:15 AM
In the Spec lines, certain cars are given specific alternates such as larger sizes for rotors/drums. This overrides the PCS.


Don,

I'll throw this out again. Based on your logic above, a full-prep GP or FP Spitfire would only be allowed to run 7" or 8" rear drum brakes. Ask Sargis or Allen if they're running rear drums or their cars.

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

Bill Miller
08-30-2004, 06:50 AM
Originally posted by Drew Aldred:
Yep, on both counts. Although alot of guys have gone to the disc setup with their full prep cars - I just haven't gotten around to it YET. My only point about the other issue you have with me Bill is that if you see or hear something about someone's car that's in the grey area, it may not be the best idea to post it on a public forum.






Well there you go Drew. I posted exactly what the PCS says about the Spit brakes. By the logic that people are using here against l-p cars, the Spits aren't allowed to use rear discs eitehr. But others have, and you are planning on converting to rear discs. Something that I'm sure you and the others (as do I) feel is perfectly w/in the rules.

I can imagine the mindset that's going on. Something to the effect of
<font face=\"Verdana, Arial\" size=\"2\">Oh, it's a limited prep car, they couldn't possibly have meant to allow that.</font>

And they may well not have intended to allow it, but I'm inclined to agree that the rules, as currently written, do provide for it. At the very least, as I stated above, you can make a good case either way. Although, I do beleive the case for allowing it is stronger, given the current rules.

As far as mentioning it here (or anywhere else for that matter), why not? My only fault was A) mentioning the class, and possibly B) mentioning the race. It was only after people began speculating and germinating rumors that it was Johannes Kraus, that I said it wasn't a VW. I never did say who it was, or what kind of car it was. Again, because I didn't feel it germane to the discussion at hand.

If anything, some of the comments here have shown that it's pointless to discuss gray areas of the rules on an internet forum.

And I still want to know how you figure I'm the bad guy for asking about this. Do you consider one driver that protests another the bad guy? Do you consider the tech official who DQ's a competitor because of an illegal part, the bad guy? Would you rather see someone get to impound at the Runoffs, only to be tossed because of something that may have been clarified sooner?


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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

hornerdon
08-30-2004, 10:05 AM
Originally posted by Bill Miller:
Don,

I'll throw this out again. Based on your logic above, a full-prep GP or FP Spitfire would only be allowed to run 7" or 8" rear drum brakes. Ask Sargis or Allen if they're running rear drums or their cars.


OK. I spent some time with the PCS, and I see where you're coming from.

The PCS allows rear disc conversions if you have rear drums. I think we all agree about that.

The Spec lines override the PCS. We all know that.

The Spec lines for limited prep cars, in the column ""Brakes Std." calls out "Factory Spec @ all 4 wheels". Because the Spec Line overrides the PCS, rear disc conversions are not allowed.

The Spec Lines for ALL full prep cars call out specific dimensions for "Brakes Std."; these happen to be the factory specs, and are defined for all 4 wheels. While the method of listing is different, this is saying exactly the same thing as "Factory spec @ all 4 wheels". The difference is that they got lazy with limited prep cars and make the owners and tech guys look up the factory specs, instead of listing them.

However, because the factory spec dimensions are listed in the Spec line, they override the PCS, so NO one can convert to rear discs, unless they have something listed in the "alternate" column.

"WAIT A DARN MINUTE!" all the full prep guys scream. "The 'Brakes Std.' column is just a description of what is standard, and doesn't override the PCS! We can convert to rear discs!"

OK, reply the limited prep guys, "if the 'Brakes Std.' column does not override the PCS, then the 'Factory spec @ all 4 wheels' statement does not overide the PCS, because it's in the Brakes Std. column. We can convert to rear discs, too!"

Am I finally catching on to what you are saying?


------------------
...Don

[This message has been edited by hornerdon (edited August 30, 2004).]

Knestis
08-30-2004, 11:02 AM
Hey - I like a good academic argument as much as or more than the next guy but I really don't like the idea that I need to spend racing budget, put a part on the car, then wait for a protest before I have a real understanding of the "truth." That's a different world than is arguing on the 'net and one for which I'm not ready.

Kirk the Wimp

racer_tim
08-30-2004, 02:13 PM
Kirk, the only reason I converted by ITB VW GTI was for the opportunity to race Nationals. I also choose to run in other than IT groups because there tends to much less body contacts when you run with more expensive cars.

I'm not knocking IT, those were just 2 of my reasons to convert. Oh year, slicks are way more fun than DOT tires.

Small more here in San Francisco runs with SRF's @ Thunderhill and Sears Point, and because of the sound requirements, we still run with with Big Bore @ Laguna Seca.

Heck, the only body contact I've had was when we run with the SS and T cars.

It's just another "playground" with different people bitching about different technical things.

Same ol' SCCA stuff




------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

Bill Miller
08-30-2004, 07:40 PM
Yes Don, I'd say you've got it. I also spoke w/ a friend of mine who's on the PAC, and he pretty much concured w/ my analysis. BTW, his opinion is that you cannot turn-down or back-cut the valves, as Mark suggests (in a limited-prep car).

Kirk,

You actually don't have to do that. Send the $250 to Topeka, and they'll tell you if it's legal or not.

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

hornerdon
08-30-2004, 11:59 PM
Originally posted by Bill Miller:
BTW, his opinion is that you cannot turn-down or back-cut the valves, as Mark suggests (in a limited-prep car).

Well, I guess if I was still building a car, I'd just have to buy some valves that already have a smaller stem and a different profile on the back of the head. My justification is actually in the limited prep spec line. First, the note talks about the head. Then, the manifold. Then, as an obviously separate issue, it sets the limits for valves, keepers, springs and pushrods -- they have to be ferrous. Other restrictions on head size are also in the spec line in another column. Then it calls out stock rocker arms and other components, which it wouldn't have to do if they were considered part of the head. And, of course, the cam is obviously considered a separate compenent and not part of the head, even with an overhead cam engine. Otherwise, the entire cam would have to stay stock except for the increased lift.

As I said, all this is in the Spec Line, so there are no questions about precedence like with the brakes. I'm absoultely convinced that you can take any valve and modify it any way you want, as long as the head diameter ends up as specified, and it is of ferrous material (no titanium). And, of course, as long as it still fits... http://Forum.ImprovedTouring.com/it/biggrin.gif


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...Don

Bill Miller
08-31-2004, 06:35 AM
<font face=\"Verdana, Arial\" size=\"2\">Well, I guess if I was still building a car, I'd just have to buy some valves that already have a smaller stem and a different profile on the back of the head. </font>

Don,

Please tell me how it matters if you modify the valves yourself, or if buy 'pre-modified' valves?

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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

hornerdon
08-31-2004, 09:23 AM
That was an attempt at deadpan humor. You reported that your contact did not favor back cutting nor reducing the size of the stem, so I figured if the valve was already made that way, he wouldn't mind....I was just being a smart aleck...

Most of the PAC members are full prep folks who struggle with the limited prep stuff. Tim is the only limited prep guy on the committee and he takes a much more cautious and conservative approach than most. And, of course, no one on the CRB, nor most tech inspectors, nor the announcers at the Runoffs, have a clue.


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...Don

[This message has been edited by hornerdon (edited August 31, 2004).]

racer_tim
08-31-2004, 11:05 AM
Actually, Brian Culbertson is also on the PAC.

I see the loop holes here. In LP on the car classification line, it says "Cylinder head prep to IP specs except that the head may be milled to achieve max. comp. ratio." and "Valves, keepers, springs, and tappets/shims to be ferrous-no titanium alloys."

IT Head prep is different than valve prep. So, I can see that back cutting the vales would be OK since it is not part of the "head"



------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

hornerdon
08-31-2004, 11:19 AM
Oops, I missed Brian. But, he can be as conservative as you, Tim. Not that that is a bad thing -- we need folks to keep limited prep from going down the same road as full prep.

In this case, I think the loophole was deliberate. I remember a discussion about this on the old volkswagenracer board, in which someone asked about using 7mm guides and valve stems instead of 8mm, if I remember the numbers correctly. Basil responded that the 7mm guides would be illegal, but threw very strong hints about accomplishing much the same thing in other ways -- such as the cutting of the valve stem where it doesn't go through the guide. Basil was on the CRB at the time and can be considered the father of the 2nd generation limited prep rules.

Basil threw in plenty of wiggle room in the limited prep rules, once telling me that no one would be really successful with a limited prep program until they had tested out at least 6 different cam configurations. This is because the cam rules are kind of impossible -- no one has ever designed a decent cam without also increasing the valve size, porting and using a different intake manifold...


------------------
...Don

racer_tim
08-31-2004, 11:31 AM
I agree Don. It was the 7mm vs 8mm valve and guide thing. I also don't think that the LP cars would be very competitive for a while, simply because the rest of the "status quo" who have been racing older british cars for years, and have spend THOUSAND's of $$$'s on them, wouldn't want to be blown away by a hot IT car (LP car).

I see both sides to this point. We need LP in order to keep participation at a decent rate, because not everybody can afford to buy and run a Huffaker Midget. But we don't want to piss the old guard that has been the backbone of SCCA for so many years.

The entire "stock box but internals are free" I see as the biggest PITA. We won't get any competitive adjustments until we spend $10k for a dog box with custom gears, ratio's.

This is EXACTLY why production got to where it is, and they are doing the same thing to LP.

I'd like to see other competitive adjustments instead of loosing weight. If LP was designed to keep the costs down, then why should we have to go with figerglass parts and Lexan in order to get the car down to min weight? I'd rather see other standard parts, like letting the "G" grind cam on the LP VW 1.8 motor. We would spend tons LESS development $$$'s with off the shelf cams.

Oh well, I'm only 1 voice in the wilderness, and sometimes I can't see the forest from the trees.

------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

[This message has been edited by racer_tim (edited August 31, 2004).]

OTLimit
08-31-2004, 12:21 PM
Originally posted by racer_tim:
Oh well, I'm only 1 voice in the wilderness, and sometimes I can't see the forest from the trees.



Tim,
You aren't the only one, you just live to far away to hear the discussions that go on at our house. http://Forum.ImprovedTouring.com/it/smile.gif



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Lesley Albin
Over The Limit Racing
Blazen Golden Retrievers

eprodrx7
08-31-2004, 12:48 PM
Although Tim is a small bore LP guy I will remind you that Tony Rivera, John Brake and myself are all LP racers also.

Greg Gauper
08-31-2004, 01:20 PM
As I posted on the prod site, perhaps the rule would be more clear if the 'powers that be' deleted the words "IT head prep" from the rule and just keep the "no porting/polishing, port matched to 1" depth only, head may be milled ANY amount to achieve desired compression" and leave it at that.

[This message has been edited by Greg Gauper (edited August 31, 2004).]

hornerdon
08-31-2004, 01:39 PM
Originally posted by eprodrx7:
Although Tim is a small bore LP guy I will remind you that Tony Rivera, John Brake and myself are all LP racers also.

Yes, John, I thought of that when I said what I said, but this discussion has been about 2nd generation LP, which applied primarily to F, G & HP. There's Limited Prep (the first batch of EP cars), then there's Limited Prep (the EP Miatas), then there's Limited Prep (the Caterham), and then there's Limited Prep (the second generation). You're Limited Prep (first batch), and that's a different can of worms.

I stick by my statement that the majority of the PAC struggles with 2nd generation Limited Prep. I can accept that you are in the minority that struggles less. Follow any discussion on Limited Prep, however, and no matter who is responding, the predominant attitude is confusion.



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...Don