Help with Production Limited Prep rules

[Bill Miller]

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!

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

[ddewhurst]

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
David

[Greg Gauper]

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]

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.

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

[racer14itc]

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

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

[ddewhurst]

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]

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]

<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?

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

[Drew Aldred]

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]

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
David

[Bill Miller]

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]

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.

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]

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.

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

[racer14itc]

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

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

[Drew Aldred]

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]

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]

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]

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

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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]

Mark,

Is this what you are doing?



Tom

[Tom Donnelly]

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