Restrictors Recommended for 2015

[R. Pare]

Ironically f3, and renault cars have inlet restrictors and have heavily regulated rules.

The difference being that it is the same restrictor for all engines, and it chokes them down quite a bit.

[BeerBudgetRacing]

The difference being that it is the same restrictor for all engines, and it chokes them down quite a bit.

So if everyone ran the same restrictor wouldn't that bring parity to the engines?

The problem is FB racers don't want to go slower...

[Daryl DeArman]

So if everyone ran the same restrictor wouldn't that bring parity to the engines?

That was the argument made by some experts in the beginning. The claim basically being that the engines are relatively the same 1000cc 4-cyl 4-stroke motors with reasonably similar compression ratios, only so much air, blah blah blah.

I thought differently, but didn't have near the dyno time these experts have. Heck, the last dyno I ran was an old GoPower water brake dyno with a buick V6 odd-fire on it.

These engines all have different porting, cam profiles, compression ratios, trans ratios (rpm splits), stock manifolds, etc. If they are after resemblance of parity they are going to need different restrictors for different engines, and new engines being introduced every year means constantly moving goal posts and all the bickering and politicking that comes with that. Sounds like fun!

Here we are, all 1000cc 4cyl 4stroke bike engines and how many different restrictors?

[BeerBudgetRacing]

That was the argument made by some experts in the beginning. The claim basically being that the engines are relatively the same 1000cc 4-cyl 4-stroke motors with reasonably similar compression ratios, only so much air, blah blah blah.

I thought differently, but didn't have near the dyno time these experts have. Heck, the last dyno I ran was an old GoPower water brake dyno with a buick V6 odd-fire on it.

These engines all have different porting, cam profiles, compression ratios, trans ratios (rpm splits), stock manifolds, etc. If they are after resemblance of parity they are going to need different restrictors for different engines, and new engines being introduced every year means constantly moving goal posts and all the bickering and politicking that comes with that. Sounds like fun!

Here we are, all 1000cc 4cyl 4stroke bike engines and how many different restrictors?

I've always liked the idea of restrictors - but let me qualify that

We can all agree restrictors mean limited airflow.... That's the gauge....
So, what comes after the restrictor should be OPEN....

Specify a restrictor and displacement. PERIOD.

After that, the engine should be open. Any cam, stroke, bore, porting, etc.
Obviously advantage goes to low end torque/power.

Wouldn't that allow parity AND creativity AND allow any and all future motors?

[jchracer]

I've always liked the idea of restrictors - but let me qualify that

We can all agree restrictors mean limited airflow.... That's the gauge....
So, what comes after the restrictor should be OPEN....

Specify a restrictor and displacement. PERIOD.

After that, the engine should be open. Any cam, stroke, bore, porting, etc.
Obviously advantage goes to low end torque/power.

Wouldn't that allow parity AND creativity AND allow any and all future motors?

Oh please no, no and no....now you are into fully built motors and all that cost……

I have sent in my letter to the board. If we must have restrictors, it should be a common restrictor for all engines. The restrictor size can be made smaller over time to control speeds if that is a requirement....although I don't agree that it should be.

If a common restrictor is specified, people will still develop new engines as time goes on and that is a good thing. I consider these engines expendable items.....unlike built motors. If someone develops a newer, slightly more powerful engine, I will move to that engine when I wear out my current engine….I don’t see what the big deal is……they don’t last forever. If new engines continually come into the class, engine costs will stabilize and maybe go down…..not up. Different restrictor sizes just kill the incentive to develop new engines and leads to all the whining you read in these four pages of posts.

Just my 2 cents.

[BeerBudgetRacing]

Oh please no, no and no....now you are into fully built motors and all that cost……

Only if someone wants to. But it opens up supply to any 1.0 big motor....

[Daryl DeArman]

...and costs through the freakin' roof....and an end result no slower than where they are now.

[Jnovak]

The restrictors on F3 motors are very different and they are also VERY SMALL. The F3 engines all use the same size restrictor on a common size plenum. These are FULL RACE engines that would make over 300 HP unrestricted and restricted make about 210 to 220. So the reality is that ANYTHNG GOES inside the engine so they all eventually wind up with the same HP because the airflow is sonic limited. These engines are also very expensive approaching new costs of F Atlantic motors.

The FB engines and restrictors are a very different kettle of fish. The typical Suzuki FB with proper headers etc makes about 175 to 180 hp at about 12,500 rpm max. Your typical Kawasaki (later model) with headers etc makes 195+ hp at about 13,500+ rpm.

Their torque curves however are very different, their gear ratios are also very different thus the restrictors required to produce the SAME LEVEL of TORQUE to the rear wheels at the same speed are different. Thus the 42mm for the Suzuki and the 40mm for the Kawi.

The 42mm on the Suzuki knocks about 3 hp off of the top end of the motor while the 40mm on the Kawasaki knocks about 10-12 off of the top end. This still gives the Kawi motor a peak power advantage but since it does not have the lower rpm torque of the Suzuki the net effect is that the torque to the rear wheels is just about line on line. Now all this does is EVEN OUT THE MOTOR OUTPUT TO THE REAR AXLE. It doe not compensate for the fact that the Kawi motor installed in a car weighs about 25 lbs more than a Suzuki. So this means that a car that cannot make minimum weight with a Kawi motor will be at a disadvantage PERIOD. This has NOTHING to do with the motor output.

The goal we were given was to equal out the motors and at the same time keep the peak power close to where is was without restrictor. This is exactly what we achieved as DIRECTED. Now these restrictor sizes are NOT CARVED IN STONE, they can be adjusted by the CRB with a 30 day notice and this will happen if the data indicates that it is needed. It may be that the data shows that it takes a 40.5mm or a 41mm restrictor for the Kawi and or other motors.

However what the restrictor does not do is equal CARS out. The restrictors only equals engines out. For instance if a cars body package is a PARACHUTE (you know what I mean) then that car will have a very hard time being competitive with a lower drag car that has a better L/D. The restrictors will also penalize a car that is overweight more than a car that can run at minimum weight. These have NOTHING to do with POLITICS or FAVORITISM is has to do with PHYSICS and nothing else.

You may not like the concept of restrictors but I am convinced that this will lead to better cars at lower costs with more competition between cars and drivers.

My own personal opinion it that a minimum weight car with a good aero package and a newer Kawasaki will be the package to beat. However if your car is a parachute and it is 40lbs over min weight then you are Fu***d.

This is physics not politics or favoritism.

[jchracer]

The goal we were given was to equal out the motors

I guess that is what I am having issues with. I think that trying to equalize the engines will never be fair, will always lead to the kind of whining we have now and upset many people. That process kills any incentive to develop new engines because people know that if they do a really good job, they will have the real potential to get slapped with a smaller restrictor than the someone running an established package…..so the established engines get more scarce and the prices go up. Plus, you know that statistical variations from engine to engine (same make and model) can have a real effect on performance. I still don’t understand how you are choosing different restrictor sizes with what I can only assume are very small sample sizes. How do you know that you are not comparing a really good Kawi to an average Zuki? The whole process just seams arbitrary and fraught with statistical variation that can cause unintended results.

I would much rather we try to equalize potential rather that outcomes…..a common restrictor size would do that.

[BeerBudgetRacing]

People choose their combination of engine, chassis & aero.....

If they make a poor choice, why is it everyone else's problem?

Give people a common formula - not a spec.....

[ghickman]

Does any one know where to even buy the plates? And what was the final decision
on what engine uses what plates.

I have the 42mm restrictor plates in stock if anyone needs them.

Contact me by email

[billwald]

There will never be 100% for or against this issue. It sounds to me like Jay and the CRB have spent a lot of time and effort trying to resolve the problem. I know they have consulted with several engine builders as well. There will probably be adjustments made as they process more data. I say trust your CRB as they are trying to do the right thing for the class long term.

People have choices in shifters, tire sizes, compounds, wings, flaps, etc. If you are in the club to stay you have a choice of classes too. I don't see a lot of whining on this thread, I see people voicing their opinions and concerns. That's a great thing. Jay has responded clearly and politely.

Thanks.

PS: I wish the runoffs were in Sebring vs Daytona!

Gary, we need a few for our new GDRE motor. PM me?

[Jnovak]

I guess that is what I am having issues with. I think that trying to equalize the engines will never be fair, will always lead to the kind of whining we have now and upset many people. That process kills any incentive to develop new engines because people know that if they do a really good job, they will have the real potential to get slapped with a smaller restrictor than the someone running an established package…..so the established engines get more scarce and the prices go up. Plus, you know that statistical variations from engine to engine (same make and model) can have a real effect on performance. I still don’t understand how you are choosing different restrictor sizes with what I can only assume are very small sample sizes. How do you know that you are not comparing a really good Kawi to an average Zuki? The whole process just seams arbitrary and fraught with statistical variation that can cause unintended results.

I would much rather we try to equalize potential rather that outcomes…..a common restrictor size would do that.

The guy who did our dyno work has done many runs on many different engines. Are there variabilities, sure but so far the do not seem huge. That said, what you are talking about is not at all what the task we were given by the CRB, which was twofold, control the top end power available so that the did not get faster except through chassis and aero development and try to equalize the multiple motors. The results achieved the goals we wre given. If you are unhappy with the goals you should work with the system to change or remove those goals. The only way to do that is to write letters stating your thoughts on the subject.

The CRB and the BoD essentially guide the direction that all the classes are moving on rules and technical matters.

[jchracer]

The guy who did our dyno work has done many runs on many different engines. Are there variabilities, sure but so far the do not seem huge. That said, what you are talking about is not at all what the task we were given by the CRB, which was twofold, control the top end power available so that the did not get faster except through chassis and aero development and try to equalize the multiple motors. The results achieved the goals we wre given. If you are unhappy with the goals you should work with the system to change or remove those goals. The only way to do that is to write letters stating your thoughts on the subject.

The CRB and the BoD essentially guide the direction that all the classes are moving on rules and technical matters.

Yes, and I have done so. I encourage others to do the same.

Thank you Jay for all the work you have put into this.....I think we all do really appreciate all your efforts......even if it doesn't sound that way. You will never please everyone.

[JerryH]

Any waterjet or cnc facility can easily make them.....or you can buy them from Gary Hickman, Chris Ferrel, your engine builder.....and no doubt some others.

The restrictors are a simple piece of.060 thick alum.......the same od as the throttle body with a 42mm id. It sits on the throttle body, and the velocity stack/air box sits down over them as it slides over the throttle body.

Jerry


QUOTE=david oleary;455165]Does any one know where to even buy the plates? And what was the final decision
on what engine uses what plates.[/QUOTE]

[Jnovak]

Thanks for the many comments and suggestions about the subject and on our efforts. The FB. Ad hoc committee is composed of a bunch of very serious drivers, engineers, builders, crew people, owners etc. I can guarantee you that each and everyone of the members of the committee want FB to be the best of the primeir open wheel classes in the club. The potential is certainly there.

I can Tell. you for a certainty that there have been many dissenting opinions on the ad hoc committee but frankly we continued to discuss and argue things until we had consensus. There have been many really good ideas discussed on this forum and we just need to make sure that they are communicated to those who make the decisions.

Let's race!

[Jnovak]

Dave Piontek of Piontek Engineering has made many intake restrictors. His email is:

davepiontek2 at gmail dot com.

[Daryl DeArman]

If they are after resemblance of parity they are going to need different restrictors for different engines, and new engines being introduced every year means constantly moving goal posts and all the bickering and politicking that comes with that.

However what the restrictor does not do is equal CARS out. The restrictors only equals engines out.

<SNIP>

These have NOTHING to do with POLITICS or FAVORITISM is has to do with PHYSICS and nothing else.

Please allow me to clarify my above statement. When I said "resemblance of parity", I was speaking to engines only. As someone opposed to "competition adjustments", it is primarily because of 2 reasons: (1) penalizing those who did their homework and (2) on-track data is utilized and way too many uncontrolled variables in that equation.

The context I am speaking of bickering and politicking is the constant debate and conflict between those who feel like they are at a disadvantage and those that are perceived to have an advantage.

[Northwind]

The restrictors are a simple piece of.060 thick alum.......the same od as the throttle body with a 42mm id. It sits on the throttle body, and the velocity stack/air box sits down over them as it slides over the throttle body.

Jerry


Ah Houston.....We may have a problem here:

• The restrictor plate must be located between the throttle body or carburetor and the engine within 4 inches of the centerline of the carburetor or fuel injection butterfly.

Per GCR Flat Plate Restrictors Page 167.

[Jnovak]

The restrictors are a simple piece of.060 thick alum.......the same od as the throttle body with a 42mm id. It sits on the throttle body, and the velocity stack/air box sits down over them as it slides over the throttle body.

Jerry


Ah Houston.....We may have a problem here:

• The restrictor plate must be located between the throttle body or carburetor and the engine within 4 inches of the centerline of the carburetor or fuel injection butterfly.

Per GCR Flat Plate Restrictors Page 167.

There is not a problem with this. However there is a very slight reword coming through very soon that clarifies any ambiguity. One of several items that have been brought up in this forum.

[Northwind]

[Zcurves]

I'm interested in the "clarification" of ambiguity. On the Suzi K9 and up, it seems the best place for a restrictor is between the TB and engine. Easy to install, easy to police. Just pop the TB and pull it out for inspection.

Am I the only one who has issues with the 30 day notice rule? I don't claim to be the most knowledgeable concerning engines, but shouldn't they be tuned to the restrictors? If my engine is being prepped by the builder, no problem. He can tune to the restrictors of the month. What happens if the regulation changes two weeks later, after it is already installed in the car? Sure I can have new restrictors made at the local machine shop, but who's going to tune the new setup? So now I have to find someone with a dyno and the expertise to tune the new restrictor/engine combo and pay that additional expense? How often is that going to happen, no more than 12 times a year? Those that have the equipment and background may be able to easily accomplish this task, but what about the rest of us?

[JRMarchand]

It cant possibly be cheap to develop a highly competitive restrictor engine package, a lot of black magic there I think. A lot of us will struggle until engine builders develop maps, headers, air boxes, velocity stacks, ram air and all sorts of goodies, some will spend hundreds of hours on the dyno playing the fiddle with restrictors. It cant be as easy as slapping the plate on and leaning the engine until a sweet spot is found.

Im curious about the clarification.

[jchracer]

One month until race time and still no official word on when this rule takes effect.......nice planning!

[Terry Hanushek]

Joel

One month until race time and still no official word on when this rule takes effect.......nice planning!

See post 93 in this thread

Terry

[Jnovak]

Joel



See post 93 in this thread

Terry

Terry, the crb post was just a pretend exercise.

[jchracer]

Joel



See post 93 in this thread

Terry

Yes Terry, I have read that. Unless I am missing something, those are proposed changes that have not yet been enacted.

How do we get an official stand on when these rules will go into effect......and more specifically, will they be in effect for the January 2015 Majors races in Florida? Forgive me if I am not up to speed on the SCCA rule change procedures.

[Terry Hanushek]

Joel

Yes Terry, I have read that. Unless I am missing something, those are proposed changes that have not yet been enacted.

How do we get an official stand on when these rules will go into effect......and more specifically, will they be in effect for the January 2015 Majors races in Florida? Forgive me if I am not up to speed on the SCCA rule change procedures.

The point that I was trying to make is that the recommended change for FB restrictors was approved by the BoD in their 10/31-11/1 meeting and will be effective 1/1/15.

I believe that the confusion on this point comes from the manner in which it has been presented. There is a single document on the SCCA website named Club Racing Recommended Rule Changes. It is a cumulative listing of all recommendations forwarded to the BoD by the Club Racing Board. Many of already been passed by the BoD; others are awaiting BoD consideration. There are internal notations to indicate the status of each specific item. It is a very difficult document to use.

HTH

Terry

[Daryl DeArman]

http://scca.cdn.racersites.com/prod/...k-Jan%2011.pdf

Pg. 42

Did I just read that NO RESTRICTORS in 2015 for FB...at least for now?

Engines frozen at 2014...

if a competitor wishes to utilize a 2015MY engine they need to write to request allowance with supporting dyno results.

[ghickman]

This is a smart decision from the SCCA.

[Jnovak]

Try this on for size.

[DonArm]

As part of the FB Ad-Hoc committee, I would recommend that you not be to concerned with the prior post.
Numbers are just numbers, these can be manipulate in any number of ways. And if that needs to be presented I can.
The dyno sheets that I put up are from a completely different dyno by a competely different tuner and are from unrestricted motors also. And by someone who has absolutely NO ball in the FB game. Someone completely neutral.
In the end hopefully performance on the racetrack will have the final say. But if one motor does become dominate I'm sure you will see restrictors come into play.

Thanks,

Don

[Jnovak]

As part of the FB Ad-Hoc committee, I would recommend that you not be to concerned with the prior post.
Numbers are just numbers, these can be manipulate in any number of ways. And if that needs to be presented I can.
The dyno sheets that I put up are from a completely different dyno by a competely different tuner and are from unrestricted motors also. And by someone who has absolutely NO ball in the FB game. Someone completely neutral.
In the end hopefully performance on the racetrack will have the final say. But if one motor does become dominate I'm sure you will see restrictors come into play.

Thanks,

Don

This sounds to me like you are accusing someone of manipulating the data Don. Now you have the same raw data that I have that was sent to all of us on the committee by a very reputable engine tuner.

This data is not from a chassis dyno but is measured at the transmission output shaft so there are no tire or chain losses. On another note the SCCA has used this gentlemans data for other classes for quite some time with no problems.

[allof6]

Who did the dyno testing?

[JRO183]

I would like to give props to the CRB/BOD for following what the FB majority wanted. It is encouraging to me going forward that, as a group, we can help direct the class.

Merry Christmas all

[RobLav]

This is a win for freedom and liberty against the oppression of excessive rule-making.

In comparing Jay's dyno graph, the owner of the car ought to retain the right to choose between the Suzuki or Kawi - with each engine having its own set of benefits, costs, and risks.

Congratulations to SCCA leadership!

[JRMarchand]

Man this is quite a relief. Merry Christmas

[Mike B]

Just for grins, I created another F1000 rules survey:
https://www.surveymonkey.com/s/3NRP88Q

[Northwind]

You should add in two more questions:

1. What is your current season budget:
$5,000-10,000
$10,000-20,000
$20,000-30,000
$30,000-50,000
$50,000-or more.

2. What level budget would force you to drop out of the class?

[Jnovak]

I am not upset at the club for holding off on restrictors. In fact I have stated to the FSRAC that this decision was the correct decision due to timing issues.

What I am upset about is that we (the FB ad hoc committee) were given the very well defined task of evening up the engine power and limiting the power so that the class would not get much if any faster. We worked very hard on that task and spent a lot of our own money and time doing research and testing. We also achieved the goals defined to us by the CRB.

Now it may be that there will never be restrictors in FB and if that is the case then the FB community can expect to go through a new engine of choice every couple of years and I have no problem with this.