Restrictors Recommended for 2015

[S Lathrop]

MEMO to all FB drivers:
The SCCA thinks we are going too fast. Restrictors are coming because we have been deemed as too fast.

This is spot on.

The FB committee was charged with the task of keeping the FBs at the current performance level.

The threat was to combine FB and FA if the FBs continue to get faster.

I happen to think that the FB will continue to improve their lap times as the class matures. That is regardless of any engine improvements that may come along. I also think that FA will not improve much unless the engine rules are tweaked some more.

The other argument in favor of the restrictors is that it will help keep a parity between the engines we have now and newer engines that come down the road. I happen to think this is a very good argument in favor of restrictors. We need a supply of current engines but we don't want to "force" people to change engines every few years as the new engines out perform what we have in the class now.

So the long term issue will be to live with restrictors or be merged with FA.

Members of the committee spend a lot of time and money working up the proposal that is on the table now. The small restrictor for the "other engines" was simply that there was not enough data to set a restrictor size for those engines. But there is a procedure to do that. If you want a different restrictor size for you favorite engine you can do it.

[JohnPaul]

I think that FB should go to a sealed 2011+ ZX10 engine. Done. Forget 07-08 GSXR. And I don't buy the whole "it's expensive" to swap out of the Suzuki. I don't know one driver running Majors that isn't dropping serious $$$ on the gsxr's. On average I'd say they go through at least 2+ motors a season (some a weekend). At least the ZX10's aren't tired old motors and always a bunch available at very reasonable prices.

[Gearslingr]

If we 'could' get a motorcycle manufacturer to 'supply' our class with engines it would be a great thing.... just using Honda as an example knowing they are supplying the Formula F series now. Even if we had something like that... I believe we'd still have to look into the Power / Weight ratio aspect of things with the different motors. Comparing all of the different Engines available and what they weigh is what decisions we all have to make. Knowing the Kawi's are heavier and having to use a Dry sump system adding even more weight is why I'm still not convinced kawi is the answer. I would opt for a Honda first to keep weight down first. I can't see 'any' advantage in gaining ~10-20 HP with another engine when you have to negate it all by adding ~40-60 more lbs of weight.
Does this make sense to anyone else?
I think it all comes down to a Power to Weight Ratio, pure and simple.

[ghickman]

If your current car with a wet sump Suzuki power is already overweight you will most definitely be way over with the Kawasaki. Then add a restrictor and you will see no performance advantage.

The upside going to the Kawasaki is future availability of low mileage donors. The Kawasaki may prove to be more robust than the Suzuki over time.

[Jnovak]

This is spot on.

The FB committee was charged with the task of keeping the FBs at the current performance level.

The threat was to combine FB and FA if the FBs continue to get faster.

I happen to think that the FB will continue to improve their lap times as the class matures. That is regardless of any engine improvements that may come along. I also think that FA will not improve much unless the engine rules are tweaked some more.

The other argument in favor of the restrictors is that it will help keep a parity between the engines we have now and newer engines that come down the road. I happen to think this is a very good argument in favor of restrictors. We need a supply of current engines but we don't want to "force" people to change engines every few years as the new engines out perform what we have in the class now.

So the long term issue will be to live with restrictors or be merged with FA.

Members of the committee spend a lot of time and money working up the proposal that is on the table now. The small restrictor for the "other engines" was simply that there was not enough data to set a restrictor size for those engines. But there is a procedure to do that. If you want a different restrictor size for you favorite engine you can do it.

Pay attention to what Steve has to say.

[Gearslingr]

Gary, right now I'm making weight at 1020 lbs wet with the GSXR. I'm also 6'2" and 210 lbs., so I'm good to go with the GSXR for now... I can't see going to any other engine that will just add more weight and negate the HP gain. I think in time we'll see other engines (maybe even the new 2015's) come into play.

Doug

[ghickman]

Gary, right now I'm making weight at 1020 lbs wet with the GSXR. I'm also 6'2" and 210 lbs., so I'm good to go with the GSXR for now... I can't see going to any other engine that will just add more weight and negate the HP gain. I think in time we'll see other engines (maybe even the new 2015's) come into play.

Doug

This is a good example of how you most likely would suffer a large weight penalty going to the Kawasaki.

Pay attention to what Steve has to say.

This is something I've been posting about for over a year now on Apexspeed. The SCCA says we are too fast and they are bent on slowing us down.

The problem I see is that it may have a negative affect on guys with dollars bringing new engines into the class. Lets face it they do it to have a performance advantage, albeit a small one.

I also don't see we will get any (engine knowledge base) trickle down from P1 like we did with DSR.

[Tony Moore]

Pay attention to what Steve has to say.

I'll paraphrase JRO on an earlier question. What is too fast? I don't see any dramtic increase in speed or decrease in lap times over a 7 year period.

So, now let me ask another restrictor question. Companies being competitive, will develope higher horsepower from time to time. Fast forward another 5 years and Kawasaki is squeezing 220HP out of 1000cc. Impossible you say? I had a 1978 Suzuki GS1000E back in the day. It was a "Superbike" then. It would run 11.75 @ 117mph in the quarter with an ungodley 85 HP! Wow! It was a lot of fun back then and a modern 600 has maybe 115 to 120 HP. Is that about right Jay? I know you are one of the 600 gurus, so correct my figures if needed, please.

So do we go through another round of even smaller restrictors to make sure everyone gets a blue ribbon and no feelings hurt?

Sorry if you Atlantic guys spend cubic money and get passed by an FB. We all make choices and maybe you chose the wrong class or maybe you just aren't up to the capability of the machine you chose to operate.

So, lets get it in the rule book just how fast a FA should be and just how slow a FB must be. Difficult to quantify at best!

Tony Moore

[Jnovak]

Fact: the CRB posted the FB restrictor plan in the June 2014 Fastrac

Fact: since that posting there have been a total of 4 scca members who have posted a total of 5 letters on the restrictor subject. Yes, that is a giant total of 4 members and 5 letters

Fact: 3 letters for restrictors (1 writer wrote 2 letters)

Fact: 2 letters against restrictors. Both of these letters are dated after 11-01-14

Suggestion: send your letters for or against restrictor to the CRB. You will spend hours here on ApexSpeed but you won't spend 10 minutes writing to the CRB.

Try this: http://www.crbscca.com

[KodaBear]

Fact: the CRB posted the FB restrictor plan in the June 2014 Fastrac

Try this: http://www.crbscca.com

No only this, but it has been stated here and everywhere since the beginning of the class formation that restrictors were a possibility down the road. Implementation of restrictors should not be a surprise to anyone.

[Daryl DeArman]

...it has been stated here and everywhere since the beginning of the class formation that restrictors were a possibility down the road. Implementation of restrictors should not be a surprise to anyone.

That doesn't mean they are the best solution.

There were other "solutions" offered back in the beginning, apparently those weren't favored as some referred to them as a solution in search of a problem.

Now, here we are.

I'm neither a SCCA member or a FB competitor/owner so I won't be writing any letters for/against.

I just won't be buying/racing a FB or F6 as long as restrictors and/or competition adjustments are on the table.

[Jnovak]

That doesn't mean they are the best solution.

There were other "solutions" offered back in the beginning, apparently those weren't favored as some referred to them as a solution in search of a problem.

Now, here we are.

I'm neither a SCCA member or a FB competitor/owner so I won't be writing any letters for/against.

I just won't be buying/racing a FB or F6 as long as restrictors and/or competition adjustments are on the table.

The FB. Ad hoc committee looked at multiple solutions. It boiled down to 3 out of 6 considered, the 3 finals were weight adjustments, rpm limits and restrictors. The committee went with restrictors.

[Terry Hanushek]

Jay et al

Fact: the CRB posted the FB restrictor plan in the June 2014 Fastrac

Fact: since that posting there have been a total of 4 scca members who have posted a total of 5 letters on the restrictor subject. Yes, that is a giant total of 4 members and 5 letters

Fact: 3 letters for restrictors (1 writer wrote 2 letters)

Fact: 2 letters against restrictors. Both of these letters are dated after 11-01-14

Suggestion: send your letters for or against restrictor to the CRB. You will spend hours here on ApexSpeed but you won't spend 10 minutes writing to the CRB.

Try this: http://www.crbscca.com

The BoD approved the CRB recommended FB restrictor table at its 31 Oct - 1 Nov meeting, effective 1/1/15. This action is reported in the Recommended Rules Change document on the SCCA website ( http://scca.cdn.racersites.com/prod/...014%20(2)1.pdf ). This document is a bit difficult to use but the Oct-Nov changes start on page 16; the FB restrictor changes are on the next page.

HTH

Terry

[Jnovak]

Jay et al

The BoD approved the CRB recommended FB restrictor table at its 31 Oct - 1 Nov meeting, effective 1/1/15. This action is reported in the Recommended Rules Change document on the SCCA website ( http://scca.cdn.racersites.com/prod/...014%20(2)1.pdf ). This document is a bit difficult to use but the Oct-Nov changes start on page 16; the FB restrictor changes are on the next page.

HTH

Terry

I think everyone knows Terry, some are simply not happy and are hopeing it will not happen.
Of course the real question is: How many people read this stuff even though they can very easily.

[Northwind]

The one thing that I have not seen published that needs to be looked at for compliance reasons are a definition of size tolerance and a measurement method for inspection. Just saying a restrictor has to be "X" in size does not define the requirements of the feature. What defines a legal restrictor plate? A common measurement method should also be on record to eliminate any confusion between competitors and inspectors. I would hope that there will be a published description addressing this to prevent future issues for all involved.

"Inspection Plan"

[Jnovak]

The one thing that I have not seen published that needs to be looked at for compliance reasons are a definition of size tolerance and a measurement method for inspection. Just saying a restrictor has to be "X" in size does not define the requirements of the feature. What defines a legal restrictor plate? A common measurement method should also be on record to eliminate any confusion between competitors and inspectors. I would hope that there will be a published description addressing this to prevent future issues for all involved.

"Inspection Plan"

There is a published definition of the restrictor in the GCR. There is not a defined measurement tool. At the Runoffs our restrictor was measured with a digital caliper.

[David Locke]

The one thing that I have not seen published that needs to be looked at for compliance reasons are a definition of size tolerance and a measurement method for inspection. Just saying a restrictor has to be "X" in size does not define the requirements of the feature. What defines a legal restrictor plate? A common measurement method should also be on record to eliminate any confusion between competitors and inspectors. I would hope that there will be a published description addressing this to prevent future issues for all involved.

"Inspection Plan"

GCR Appendix F. Technical Glossary defines a legal restrictor plate. See page 167 of the December 2014 GCR.

[Daryl DeArman]

No maximum thickness on the plate? No tolerance? At what temperature? How are they going to determine whether the hole is centered?

[Northwind]

Thanks David,

I found it and after reading it, can assume that the restrictor can be sized no larger than "X" (since there is no tolerance language) and can be shaped to any profile as long as it does not exceed "X" and that it must be centered within the throttle body bore. Centered being a relative term and would be difficult to enforce based on the shape of some inlet tubes. It seems a little muddy to me.

[Wren]

per the GCR section on tolerances, ID of inlet restrictors is absolute maximum.

minimum thickness is .060"

[David Locke]

No maximum thickness on the plate? No tolerance? At what temperature? How are they going to determine whether the hole is centered?

Tolerance? Temperature? I'm no expert on this, but if I were entering a car that required a maximum 42mm restrictor then it would be my understanding that the hole could not exceed 42mm under any circumstance. I would not expect a tolerance. Although the Flat Plate Intake Restrictor language is relatively new, the Single Inlet Restrictor (SIR) has been around for a long time. What is the tolerance for the inlet opening on an SIR? At what temperature is the opening on an SIR required to be tested?

Thanks David,

I found it and after reading it, can assume that the restrictor can be sized no larger than "X" (since there is no tolerance language) and can be shaped to any profile as long as it does not exceed "X" and that it must be centered within the throttle body bore. Centered being a relative term and would be difficult to enforce based on the shape of some inlet tubes. It seems a little muddy to me.

I'm not sure I understand the meaning of shaping it to any profile, but the definition specifies that "[t]he hole through which all air to the engine must pass shall be round." I'm no expert on this, but I suspect it's relatively easy to determine the center-to-center distance of throttle bodies and then determine whether the openings in the restrictor plate correspond with that measurement.

[Northwind]

I'm not sure I understand the meaning of shaping it to any profile, but the definition specifies that "[t]he hole through which all air to the engine must pass shall be round." I'm no expert on this, but I suspect it's relatively easy to determine the center-to-center distance of throttle bodies and then determine whether the openings in the restrictor plate correspond with that measurement.[/QUOTE]

David please don't take this as argumentative.
There are people that manufacture parts for a living that know exactly what I am try to get at. This is not directed at you for an answer. If we have a 42mm hole thru a .062 plate, at what size variation is the hole no longer round. Due to manufacturing process variances such as a wobbling drill bit or play in the fixture table for example, there can be a shift, and perfect circle or round form is not achieved. The hole now has a very slight oval shape. 42mm as allowed per the rules at the largest measurement and 41.98mm for the short measurement. What tolerance band constitutes an acceptable round feature for our inspection purpose. If the hole is not perfectly round how do we determine the true center point? Now that we have a questionable center point how are we going to measure for center to center position in relation to the throttle body bore. Lets take this a bit further and ask our selves how are we going to determine the true center point of the throttle body bore. It could be more out of round than the restrictor making another questionable position. Now we have to take two separate questionable center positions and join them and maintain some amount of position during assembly to be compliant to the rules. All I am trying to get at is what size tolerance is going to be permissible for the restrictor. A bilateral tolerance of 42mm +.000 and -.XXX should be given otherwise we have no definition of what is going to be accepted as round. The person manufacturing the restrictor will need to know this and so should the tech inspectors. If we are going to call out a centered requirement we also should have a position tolerance requirement between the restrictor bore and throttle body bore. otherwise it is subjective to interpretation.

[Daryl DeArman]

Tolerance? Temperature? I'm no expert on this, but if I were entering a car that required a maximum 42mm restrictor then it would be my understanding that the hole could not exceed 42mm under any circumstance. I would not expect a tolerance.

Agreed, and if you are going to make a restrictor 42mm +.0000" realize that any temperature above/below whatever it was when manufactured it will no longer be 42mm or perfectly round. Or that after being bolted-on/unbolted it is no longer going to be perfectly centered.

I understand the intent, but having rules that can't be accurately and objectively enforced result in "I'll know it when I see it" type disqualifications.

[KodaBear]

Agreed, and if you are going to make a restrictor 42mm +.0000" realize that any temperature above/below whatever it was when manufactured it will no longer be 42mm or perfectly round. Or that after being bolted-on/unbolted it is no longer going to be perfectly centered.

I understand the intent, but having rules that can't be accurately and objectively enforced result in "I'll know it when I see it" type disqualifications.

intake restrictors are nothing new in SCCA or the racing world in general. It's not like this will be the first time inspectors will have measured them.

[JerryH]

Both the ad hoc committee and the crb know adustments to restrictor sizes may be needed. This was never fixed in stone.....but good data is needed to make that decision.

We will have the opportunity next year to get some useful data on the same brand car with both a KAW and a GSXR engine.

There will be at least one Phoenix and probably a JDR with Kaw engines installed. Both can be kept to min weight.

If we look at acceleration data from slow to fast....say 50 to 140.....in the same chassis.....with the same wing settings and near same wt.....we can use that data to make adjustments if needed.

We just can't compare data from two different brand cars with totally different drag and weight. Also.....we can't just look at top speed..... or acceleration up to something less than top speed. The data has to look at the entire speed range.

It will probably take a full season to gather enough data to make a well informed decision.....but it is imperative we do so.

Until we have that data, the restrictor sizes recommended by the ad hoc committee are a very good starting point.....and are based on very good analysis of lots of dyno data, different gear ratios between engines, rpm operating range, etc.

Jerry

[Daryl DeArman]

intake restrictors are nothing new in SCCA or the racing world in general. It's not like this will be the first time inspectors will have measured them.

And it's not like restrictor plates have ever been "cheated-up" undetected either.

I don't see a whole lot of sense in rules that can't be objectively enforced. Leave the word "round" out, leave the word "centered" out. Get rid of the chamfer/radiused language as you look close enough at the edge of any hole and it's not going to be an edge perpendicular to the holes' axis.

[allof6]

Both the ad hoc committee and the crb know adustments to restrictor sizes may be needed. This was never fixed in stone.....but good data is needed to make that decision.

We will have the opportunity next year to get some useful data on the same brand car with both a KAW and a GSXR engine.

There will be at least one Phoenix and probably a JDR with Kaw engines installed. Both can be kept to min weight.

If we look at acceleration data from slow to fast....say 50 to 140.....in the same chassis.....with the same wing settings and near same wt.....we can use that data to make adjustments if needed.

We just can't compare data from two different brand cars with totally different drag and weight. Also.....we can't just look at top speed..... or acceleration up to something less than top speed. The data has to look at the entire speed range.

It will probably take a full season to gather enough data to make a well informed decision.....but it is imperative we do so.

Until we have that data, the restrictor sizes recommended by the ad hoc committee are a very good starting point.....and are based on very good analysis of lots of dyno data, different gear ratios between engines, rpm operating range, etc.

Jerry

Jerry,
What difference doe the car make in this decision? You are setting the plate size based on what the engine does on the dyno, correct ?

Based on your statements you make it sound like you want to equalize to total packages like they are trying to do in Atlantic.

If that's the case you may as well consider the class dead.

[Jnovak]

And it's not like restrictor plates have ever been "cheated-up" undetected either.

I don't see a whole lot of sense in rules that can't be objectively enforced. Leave the word "round" out, leave the word "centered" out. Get rid of the chamfer/radiused language as you look close enough at the edge of any hole and it's not going to be an edge perpendicular to the holes' axis.

Excuse me Daryl. The SCCA has multiple classes that use restrictors and have done so for many years. You are definitely looking for something that is not there.

I suggest that you get a car and go racing. You are bored.

[Gearslingr]

O.K., here's an option.... If the restrictors aren't the way to go... (not saying it is or isn't at this point) what about utilizing a simple Power to Weight Rule.

Since the rules allow any Engine up to 1000cc currently.
Since we've established a 'Baseline' Engine with the Suzuki.
Establish a 'Baseline' Power / Weight Ratio for every officially Dyno'd Engine out there.

Pwr / Weight Ratio of the Suzuki for class car weight of 1000 lbs = 5.405
Pwr / Weight Ratio of Kawi (ZX10R ~197hp?) would make your car weight = 1065 lbs.

Lets say you end up finding a motor that pumps out 210 hP... you'd have to weigh 1135.

Then there would be no restrictors needed.
This rule wouldn't care what type of car you have, what aero package you've got etc.

Catch my train of thought?

Doug

[Northwind]

Doug,

Your formula works great in straight line acceleration. However it falls apart in parity for cornering and braking. Heavier cars now start behaving differently approaching and during the corners than the lighter cars.

[Gearslingr]

Granted, but driving style, tire choices, car setup etc. is all independent to the teams and we don't restrict any of that, so imo it doesn't come into play with regards to being a relative factor in pwr / weight ratio determination.

Doug

[JerryH]

allof6:
We are not trying to equalize the cars......just bring the engines to something close to parity.....and comply with the mandate to limit speed increases in the future. Some are questioning the dyno results and want on track data used to verify the validity of the restrictor sizes chosen.....so:

Comparing different engines in the same car (with the same setup on the car) will be helpful toward that end.

Comparing them in different cars would only confuse car differences with engine differences.


Doug:
Adding enough weight to compensate for the significant horsepower differences could easily overstress the chassis and suspension components......we are cornering at 3 g. Since it effects cornering and brakeing as well as acceleration.....and therefore has a significant effect on lap times......it confuses the issue here.....which is to avoid an ever increasing horsepower war and an engine of the year scenario.


Jerry

[Gearslingr]

Jerry, understood.

[Daryl DeArman]

Excuse me Daryl. The SCCA has multiple classes that use restrictors and have done so for many years. You are definitely looking for something that is not there.

I suggest that you get a car and go racing. You are bored.

All the reason to believe that many have found ways to circumvent the rules undetected.

Why make rules that you can't objectively enforce?

As to boredom...perhaps I miss the competition, but not the politics. As soon as SCCA offers something that (1) I haven't raced before and (2) doesn't have restrictors or competition adjustments and (3) has decent competition in my neck of the woods, I am there. The Pacific Northwest in calling my name.

Until then, I will offer my opinion which you may chose to ignore, disregard or debate.

[RobLav]

I think it's about time to create a sub-class under FS... where we won't be subject to this sort of thing. There are quite a few cars out there at the performance level of FB... like other F3 cars, the Renaults, Fran Am, etc... we could a have a 1 liter spec and a 2 liter spec but all merged to one sub-class. Sort of going back to grassroots basics, where FB originated. Probably another pipe dream.

[JohnPaul]

Funny, Bill Wald (one of the original FB guys) told me last night he's going to run as an FS next year. He won't slow his car down....can't say I blame him.
I personally think the only engines that should get restrictors are any new ones that come along and crush the current gsxr and kawi.

[david oleary]

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

[KodaBear]

I think it's about time to create a sub-class under FS... where we won't be subject to this sort of thing. There are quite a few cars out there at the performance level of FB... like other F3 cars, the Renaults, Fran Am, etc... we could a have a 1 liter spec and a 2 liter spec but all merged to one sub-class. Sort of going back to grassroots basics, where FB originated. Probably another pipe dream.

Ironically f3, and renault cars have inlet restrictors and have heavily regulated rules. Not sure about fran am.

[billwald]

George Levien will be driving my car for the Winter Majors and it will be in compliance whatever the rule is. I may change my mind for my races I don't know for sure.
Last weekend I ran against a Kawi and 2 Moon built GSXR's. I used a $2K Ebay bike motor and won both races. We had a Piper, Astra, RFR and my Stohr in the field. I thought the cars were more or less evenly matched. We were down some on top speed but to me it was more of an Aero thing. I ran a lot of wing and wide tires.

Appreciate all the posts and sharing of knowledge and opinions. I know people are working hard on ideas to help the class overall not hurt it. Thanks.

PS We also set the quickest laps in both races and I weighed 1058 at the scales.

[KodaBear]

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

David ferguson makes a lot of the restrictors for the P2 guys. You can try contacting him for the plates.