Do we need to specify?

[Andy Bettencourt]

Many rules state: "May be removed or replaced".

Do we need to add 'modified'? We had an incident in tech this past weekend where some confusion was created by a literal read of the rules by the tech team. An RFA was written, the ruling was not supported by the Stewards - but they did ask me to take a look at the wording. Here is the rule in question - emphasis mine to highlight the area in question.

<div class='quotetop'>QUOTE</div><div class='quotemain'>Thoughts? Unitended consiquenses? </span>

[JeffYoung]

I think "substituted" should cover this situation and make a modified OEM tube legal. However, I would be fine in adding "modified" to that last and -- at first glance -- see no unintended consequences.

I also see, have pointed this out before, a conflict between the 2nd and 4th sentences. The second sentence says that velocity stacks, basically modified intakes on a carb to speed flow, are not legal. The last sentence says, or at least we all believe it to say, that everything in front of the carb is free so long as you don&#39;t use cowl induction, ram air (unless stock) and you pick up your air within the engine bay.

I think the intent of the "no velocity stacks" (which is defined I believe to include air horns) rule is to prohibit anything that eases or speeds up the flow of air into the carburetor or throttle body.

Hence the quandray. The last sentence allows modified hoses, tubes, etc. -- why would anyone modify an intake tube, hose, pipe, etc. UNLESS they were going to speed or ease the flow of air into the intake.

For purposes of disclosure, this is definitely a ME request, but I would remove "velocity stacks" from the second sentence as well to get rid of what I perceive as a conflict with the last sentence of the rule.

[JimLill]

I agree with Jeff.......... susbtituted gives lots of ground...........

[lateapex911]

I heard about this, and thought it was so odd that an official would choose to write paper on such an item. I understood the stock unit merely had some heat sheild added to it. Yet the tech thought that was illegal, and thought strongly enough to write it up. Weird.

To my reading, the owner removed the part, and substituted it with a stock unit that has been modified.

[Andy Bettencourt]

I also see, have pointed this out before, a conflict between the 2nd and 4th sentences. The second sentence says that velocity stacks, basically modified intakes on a carb to speed flow, are not legal. The last sentence says, or at least we all believe it to say, that everything in front of the carb is free so long as you don&#39;t use cowl induction, ram air (unless stock) and you pick up your air within the engine bay.

I think the intent of the "no velocity stacks" (which is defined I believe to include air horns) rule is to prohibit anything that eases or speeds up the flow of air into the carburetor or throttle body.

Hence the quandray. The last sentence allows modified hoses, tubes, etc. -- why would anyone modify an intake tube, hose, pipe, etc. UNLESS they were going to speed or ease the flow of air into the intake.

For purposes of disclosure, this is definitely a ME request, but I would remove "velocity stacks" from the second sentence as well to get rid of what I perceive as a conflict with the last sentence of the rule. [/b]

I will disagree. 1st: you are seperating Ram Air and velicity stacks. It says they are both prohibited. Right?

2nd: I see a difference between &#39;increasing&#39; the amount of air and &#39;speeding&#39; the air up. VStacks are used to speed the air up. So are SIR&#39;s ironically - because they are basically Vstacks. When I was designing my intake, I thought that a nice LARGE SIR would speed up the air into the TB...then I remembered that it really could be considered a VStack so I didn&#39;t go any further with it.






To my reading, the owner removed the part, and substituted it with a stock unit that has been modified.
[/b] And he did just that, the point being that it doesn&#39;t say you can modify that part. The confusion may lay in that just above that in the rules, modify is specifically mentioned so it was assumed that you couldn&#39;t by tech.

Take a look at the definition of modify in the glossary.

Modify - To change a component by reworking, but not by replacing.[/b]

[shwah]

It says you can replace the part, with no further restrictions. Clearly you can replace the part with a modified stock unit. Sounds like the tech guy just had some brain fade and made a mistake.

No need to alter the wording of the latter sentence, but maybe would make sense to remove the modified term from the former. I would leave it as is myself.

[lateapex911]

And he did just that, the point being that it doesn&#39;t say you can modify that part. The confusion may lay in that just above that in the rules, modify is specifically mentioned so it was assumed that you couldn&#39;t by tech.

Take a look at the definition of modify in the glossary. [/b]

Right, but substitute carries no limits...so substituting with a modified stock part should be legal.

[JeffYoung]

Andy, I&#39;m off topic, so last one on this and then we can continue to discuss via e-mail.

Ram air is defined in the definitions as obtaining air from outside the bodywork.

Velocity stacks are defined as anany attachment to the intake that alters the dynamic coupling between carb and the mass of incoming air.

A velocity stack is not ram air.

I would say that any device that alters the "dynamic" coupling in anyway, be it increasing or speeding up the air is a "velocity stack" under this rule. Thus, ANYTHING done to the "dynamic" -- be it speed, force, pressure, temp, would be illegal if a velocity stack as defined in this rule is prohibited. Your intake I am sure increases the air to the throttle body and is therefore an illegal velocity stack. Heatshielding decreases the temp and is therefore a velocity stack.

You could argue that the definition of "velocity stack" seems to only apply to carbureted cars but that would seem to me to be rather inequitable and should be gotten rid of.

I am telling you, there is a serious inconsistency in this rule. In one place it says, and we all agree, that you can do anything to modify the intake ahead of the carb or throttle body so long as you pick up air from in the engine bay and/or stock location. In another, it says I can&#39;t (since I have a carb&#39;ed car) do anything that modifies the "dynamic" of the air. Again, I think ANY modification to the intake track is going to modify the "dynamic" in some way.

Not arguing, just debating. I&#39;d like me some air horns, but can live without them.

[charrbq]

Here&#39;s a question. My hood is bent upward from damage in an accident. Even though it is pinned down securely, it bows in the middle of the front. It doesn&#39;t do my aerodynamics much good, but I&#39;m sure air gets into the engine area that comes from outside the confines of the engine bay. Does this constitute drawing air from outside the engine bay same as an alternate intake for the carb or other such device?

[GKR_17]

Ram air is defined in the definitions as obtaining air from outside the bodywork.

Velocity stacks are defined as anany attachment to the intake that alters the dynamic coupling between carb and the mass of incoming air.

A velocity stack is not ram air.

[/b]

So if there&#39;s no carburetor then it&#39;s not velocity stack, right? Maybe it&#39;s time to update the glossary.

[JeffYoung]

Grafton, I think that is right based on the way this very tortured rule reads right now.

The way I think it works is that an FI car can do anything ahead of the throttle body/AFM that it wants. A carb car can&#39;t do anything to alter the "dynamic" which could be any change to temp, flow, speed, etc. of the air.

That&#39;s an inequitable distinction.

Then, if you remove the "carb" limitation from the definition of velocity stack, you probably make almost all aftermarket and self made FI intakes illegal.

I guess it is time for me to put a letter to together. I think the best fix is to remove the velocity stack "prohibition" and truly make everything ahead of the carb body or AFM/throttle body "free" except for non stock ram air.

By the way, how did you guys do in the ECR? I saw the car, but didn&#39;t see any results on mylaps.

[Andy Bettencourt]

The way I think it works is that an FI car can do anything ahead of the throttle body/AFM that it wants. A carb car can&#39;t do anything to alter the "dynamic" which could be any change to temp, flow, speed, etc. of the air.

That&#39;s an inequitable distinction.

Then, if you remove the "carb" limitation from the definition of velocity stack, you probably make almost all aftermarket and self made FI intakes illegal.

I guess it is time for me to put a letter to together. I think the best fix is to remove the velocity stack "prohibition" and truly make everything ahead of the carb body or AFM/throttle body "free" except for non stock ram air.
[/b]

I don&#39;t see it that way. An FI car can change the stock tubing, remove it or add it. No Ram Air, no Velocity Stack. A carb car has no such &#39;restrictions&#39; as the air goes right from the air cleaner into the carb. This would be like me putting a cone filter on my MAF which would be connected to my TB. We both have the same two limitations. No &#39;forcing&#39; air into our engine and no &#39;speeding&#39; it up. If you want a mongo air cleaner, you can have one, your limit is cfm. If I want mongo tubes, I can have them, my limit is air metering device and TB.

I disagree that most aftermarket intakes would be illegal because they do not add &#39;velocity&#39;. They may add quantity - but only serve to try and better a poor situation a carb car doesn&#39;t have - airflow limits BEFORE the TB/carb.

[zchris]

Andy, if you increase quantity of air thru and your TB is a fixed size, you must have increased velocity. Therefore....
Chris Howard

[zchris]

And to answer the question, yes Andy. Any way you can improve the wording will help. Keep up the good work Andy. Thanks
Chris

[Andy Bettencourt]

Andy, if you increase quantity of air thru and your TB is a fixed size, you must have increased velocity. Therefore....
Chris Howard [/b]

Only if the TB is the restriction point to begin with. I know on my car it wasn&#39;t. So more air got in but it didn&#39;t get FASTER... The TB/AFM/MAF will be the restrictor. Only so much air can get through there no matter what you do with your &#39;tubes&#39;. No forced acceleration, no extra velocity. Right?

[tom91ita]

puleeze clean it up and put it to bed or stick a fork in it so we know it is done.

i was similarly given grief because i had modified my underpulley by chucking it in a lathe and cutting off the A/C portion of the pulley to lighten it.

my thought was that i had substituted it with a single pulley but instead i had installed a modified one.

[BlueStreak]

puleeze clean it up and put it to bed or stick a fork in it so we know it is done.

i was similarly given grief because i had modified my underpulley by chucking it in a lathe and cutting off the A/C portion of the pulley to lighten it.

my thought was that i had substituted it with a single pulley but instead i had installed a modified one.
[/b]

Tom,
Somebody gave you grief over a mod to a "free" item :blink: Unfriggin believable...........

[JeffYoung]

Andy, Andy, Andy, I love you man, but this is contradictory and makes no sense:



I don&#39;t see it that way. An FI car can change the stock tubing, remove it or add it. No Ram Air, no Velocity Stack. A carb car has no such &#39;restrictions&#39; as the air goes right from the air cleaner into the carb. This would be like me putting a cone filter on my MAF which would be connected to my TB. We both have the same two limitations. No &#39;forcing&#39; air into our engine and no &#39;speeding&#39; it up. If you want a mongo air cleaner, you can have one, your limit is cfm. If I want mongo tubes, I can have them, my limit is air metering device and TB.

I disagree that most aftermarket intakes would be illegal because they do not add &#39;velocity&#39;. They may add quantity - but only serve to try and better a poor situation a carb car doesn&#39;t have - airflow limits BEFORE the TB/carb.
[/b]

Where do I start? If an FI intake is adding quantity that is a "dynamic" change to the intake of air. That&#39;s illegal on a carb, why should be it legal on an FI car? In fact, I&#39;m not even sure now -- because velocity stack is so broadly defined as anything that changes the "dynamic" of the air entering the intake track -- that big old air cleaner on a carb is "legal" since it allows more quantity of air in a carb. At the very least your read on the "velocity stack" rule contradicts the free air cleaner rule, since a less restrictive air cleaner allows more (and FASTER) air in.

Nor does the distinction between a carb and an AFM/TB make any sense. They are no different. In either case, the diameter of the chokes on the carb, or the AFM/TB are the "hole" down which we are trying to put air. Under the rule as presently written, with the velocity stack prohibition being limited to carb cars, you COULD speed up the air into your AFM/TB legally. I can&#39;t.

The rule should either be everyhing ahead of the carb on carb cars, and the AFM/TB on FI cars, is free. That&#39;s simple, straightforward and clear. As written now, the rule is contradictory and a mess because ANYTHING you do to the intake is going to change the dynamic and as written that is literally prohibited on carb cars at the moment but allowed on FI carbs under a "strict" reading of the rule.

Letter to the CRB time I suppose, but I doubt this one will get cleaned up without any "help" from the ITAC.

[Andy Bettencourt]

Andy, Andy, Andy, I love you man, but this is contradictory and makes no sense:[/b]

To you...I see it clearly.


Where do I start? If an FI intake is adding quantity that is a "dynamic" change to the intake of air. That&#39;s illegal on a carb, why should be it legal on an FI car?[/b]

I just see it differently. Your car had a certain sized air-cleaner/intake system as stock. You change that intake system to improve flow 1 iota, and you have done the exact same thing as an FI car does when changing that tubing - which is also free. Did you change the &#39;dynamics&#39; of your air?




In fact, I&#39;m not even sure now -- because velocity stack is so broadly defined as anything that changes the "dynamic" of the air entering the intake track -- that big old air cleaner on a carb is "legal" since it allows more quantity of air in a carb. At the very least your read on the "velocity stack" rule contradicts the free air cleaner rule, since a less restrictive air cleaner allows more (and FASTER) air in.[/b]

Now you are starting to see my point. You can add a free air cleaner, but it can&#39;t be a VS, nor can you add a VS within your system. More air does not equal faster air when you are PULLING it with a fixed amount of &#39;pull&#39;. You are just undoing retrictions that don&#39;t allow a &#39;full pull&#39;. RA and VS&#39;s add a &#39;push&#39;. A definition of VS can be found here:

http://en.wikipedia.org/wiki/Velocity_stack

I think you will find a working definition of a &#39;dynamic change&#39; is in there. It&#39;s about the acceleration of airflow INTO the duct, not an addition in quantity.

I look at this simply (maybe so simply I am getting it wrong). Compare an intake system to people, doors, and hallways. The TB/carb is the exit point. The hallway is the intake tube and the entrance is your air filter. If you have stock, 1 door to get in, and a one lane hallway that terminates at double doors, your &#39;flow&#39; is only X mph by 1 person due to the intake restrictions even though your TB/carb will allow 2 people through. Opening up the &#39;door&#39; and the &#39;hallway&#39; to 2 people doesn&#39;t increase their pace at all, just the quantity. Not a dynamic change IMHO.

Now, as illustrated in the link, when you have a standard tube, because of the design, you don&#39;t get 100% of the &#39;people&#39; you could into the hallway because they have to take as much as a 90 degree turn to get into the hallway. This slows them down and creates turbulance. When you add a VS, you create &#39;on-ramps&#39; into the hallway and a more perfect flow - as much as 10% if you believe the website.

So after that stupid example, I think the issue here is your definition of &#39;dynamic change&#39;.


Nor does the distinction between a carb and an AFM/TB make any sense. They are no different. In either case, the diameter of the chokes on the carb, or the AFM/TB are the "hole" down which we are trying to put air. Under the rule as presently written, with the velocity stack prohibition being limited to carb cars, you COULD speed up the air into your AFM/TB legally. I can&#39;t.

The rule should either be everyhing ahead of the carb on carb cars, and the AFM/TB on FI cars, is free. That&#39;s simple, straightforward and clear. As written now, the rule is contradictory and a mess because ANYTHING you do to the intake is going to change the dynamic and as written that is literally prohibited on carb cars at the moment but allowed on FI carbs under a "strict" reading of the rule.

Letter to the CRB time I suppose, but I doubt this one will get cleaned up without any "help" from the ITAC.
[/b]

Jeff, we are just debating here. I have one opinion and you are trying to convince me otherwise. That&#39;s why there are 9 guys on the ITAC...you know better than to infer that I represent the whole group.

Neither type intake system can add RA or a VS. Both types can &#39;add&#39; air quantity by changing air filters, air cleaners and intake tubes. I just read the &#39;dynamic change&#39; differntly than you. I see no inequity in the rules (other than maybe carbed cars getting alternate allowances for uprated units), both can add quantity of air but neither can design in a way to speed that air up. Having said that, maybe a written definition of &#39;dynamic change&#39; is in order to clear up what air flow RESULT is prohibited.

To add to this - you could add the exact same intake that I have on my car, to your car and be legal. I just don&#39;t read the words that prohibit a carb car from doing anything an FI guy can.

Maybe some of the engineering guys can weigh in here. Lawyers and sales guys debating &#39;dynamic airflow&#39; may not be good! :)

[Ron Earp]

Maybe some of the engineering guys can weigh in here. Lawyers and sales guys debating &#39;dynamic airflow&#39; may not be good! :)
[/b]

I&#39;m a science guy and I&#39;ll weigh in to help you out - don&#39;t debate lawyers, it&#39;ll end up costing you in some way! :P

R

[JeffYoung]

Andy, at least you got me laughing.....I&#39;ll weigh in on the substance of this later, we do it see it diferently. I also know you aren&#39;t the ITAC, what I wrote was poorly worded, and shouldn&#39;t have said it.

Still at lot of holes in your argument though, even to this lawyer...lol....first of which is that the wiki definition of velocity stack is WAY different than the GCR&#39;s.

[Andy Bettencourt]

I am convinced the definition of &#39;dynamic change&#39; is where we are at odds. FI cars and carbed cars can both increase air flow. Neither can add a velocity stack. Increased airflow does not a velocity stack make.

[JeffYoung]

have to go work on a Lola, but one question Andy for consideration later:

Other than the limiations on ram air and taking air from outside the engine bay/stock location, what is the policy behind allowing any dynamic change to the air flow EXCEPT velocity?

In other words, wouldn&#39;t it be simpler, easier and more congruent with the rest of the air intake rules to simply say:

Intake tracks, tubes and other devices ahead of the carburetor, or AFM/TB , are free, except ram air is prohibited unless fitted as stock. Engine are pick up shall be either as stock, or within the confines of the engine compartment.

[Andy Bettencourt]

have to go work on a Lola, but one question Andy for consideration later:

Other than the limiations on ram air and taking air from outside the engine bay/stock location, what is the policy behind allowing any dynamic change to the air flow EXCEPT velocity?

In other words, wouldn&#39;t it be simpler, easier and more congruent with the rest of the air intake rules to simply say:

Intake tracks, tubes and other devices ahead of the carburetor, or AFM/TB , are free, except ram air is prohibited unless fitted as stock. Engine are pick up shall be either as stock, or within the confines of the engine compartment. [/b]

Becasue the PTB want velicity stacks to be illegal...me, I guess I could care less...seeing Jeff&#39;s car with one of these wouldn&#39;t bother me! :)



http://static.summitracing.com/global/images/prod/norm/sum-g3006_m.jpg

And we WILL ban you from this site unless you provide us pics of the Lola!!!!

[Eagle7]

What&#39;s the PTB?

[Greg Gauper]

Powers That Be....

[JeffYoung]

Ron -- get some Lola pics up for Andy and the boys. The cross over headers, and the chassis are works of art. We&#39;ve got some racing plans for this car, but that will have to stay secret for a while.

Yes, the definition of dynamic is PART of where we differ. In my view there is no way to limit "dynamic" to just velocity. It is not limited that way in the rule, and arguably covers velocity, pressure, quantity and temperature, making almost any change to a carburetor intake track illegal in my view, although this was surely not the intent.

When you replace the filter on your car with a less restrictive one, aren&#39;t you by necessity increasing the velocity of the flow? Engine vacuum can now pull air in FASTER.

I saw your point about pull vs. push, which would deal with the above and is a good thought. I think your point is you can reduce the resistance to PULL but you can&#39;t PUSH. That is the clearest explanation of why anything but a velocity stack is illegal.

Problems remain even with this though:

1. It still requires a clean up of the definition of velocity stack, which prohibits any change of the "dynamic" on carb&#39;ed cars (not just adding a push). Not to sound like a broken record, but I would think that under the current definition of velocity stack a "dynamic" change such as reducing air intake temperatur is illegal. This needs clean up.

2. There is the unnecessary limitation of the definition of velocity stack to carb&#39;ed cars. I frankly think you can speed up the air going into the intake track on an FI car right now, legally, since velocity stacks are defined only as affecting the dynamic coupling between air and carburetor. This needs clean up.

3. Last, and perhaps my best point in response to your very good push/pull distinction. Most guys (both FI and carb) "look" around the engine bay for the area where there might be high air flow, be it near the front of the radiator on the Z cars where there used to be an inlet for fresh air to the caing, to near the right front headlight on 2nd Gen ITS RX7s where the hood is bowed up a bit, to at the base of the windshield where a low pressure area draws air into the engine bay. ALL of these are seeking to put the air filter in a place where it is in a FASTER air flow. Aren&#39;t any such intake tubes, hoses, etc. that seek out such locations of higher flow WITHIN THE ENGINE BAY illegal under the push/pull theory?

It just seems to me that there is a very easy way to avoid all of this mess and just say that ram air, and picking air up outside the engine bay (unless allowed as stock) is illegal. Everything else in front of the intake track is legal.

Would you (personally) support that change/clarification?

[Monkeywrench]

Since the argument concerns velocity stacks

Is this legal?

http://us.st11.yimg.com/us.st.yimg.com/I/s...r_1952_22557201 (http://us.st11.yimg.com/us.st.yimg.com/I/saferacer_1952_22557201)

It looks like a velocity stack to me

[JeffYoung]

I would say:

1. The perception by most on this board before reading the rule would be: legal.

2. Since that sucker narrows and increases the speed of air flow, on a carb&#39;ed car this would be: illegal.

3. On an FI car, under the rule as presently written: legal.

[Ron Earp]

OK.
http://www.gt40s.com/images/lola/loalaengine.JPG

[Andy Bettencourt]

What if we took the carb-specific wording from the GCR-based definition of Velocity stack?

Mmmmmm, bundle-o-snakes. Tasty.

[Z3_GoCar]

have to go work on a Lola....

[/b]

As an aside, I though you&#39;d be interested in this. There&#39;s a shop here in our little corner of the desert that makes Lola T-40&#39;s. They just got one in a few months ago that had been the cause of several divorces :blink: Does Matrix ring a bell?

James

[JeffYoung]

James, that&#39;s funny. Cars do cause divorces I guess....

Ron&#39;s is a T-70 open top with the chassis and body panels made by Fran Hall at Race Car Replicas outside of Detroit. Fran does great, great work.

Andy, removing the carb distinction takes care of the "obvious" (to me...lol) inequity in the rule.

But it doesn&#39;t address the contradiction. In one place, the rule says that tubes, hoses, pipes, etc. in front of the carb or the AFM/TB are free. Then, it says that velocity stacks that affect the "dynamic" are illegal. Dynamic is not just velocity, it is quantity and temp. too.

I think you also need to either (a) specifically state "dynamic" for purposes of this rule only means velocity (the "push" you are talking about above) OR (B) make everything in front of the carb/AFM/TB free.

I think (a) would still cause problems simply because in my limited view, all intake systems are designed to create some push in some way, either by locating a place of higher air flow in the engine bay and constructing tubes, etc. to get the air cleaner there, or just by well designed and planned tubes and air filter mounts.

When I get some free time, I am going to write a letter on this to the CRB and see what comes of it. My position will be that everything should be free ahead of carb or AFM/TB.