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  1. #1
    Contributing Member Jnovak's Avatar
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    Default Formal proposal for 600cc MC engines

    Hi everyone. After a ton of discussion within our MC engine proposal committee as well as much discussion with several engine builders, we have finalized our proposal that we will send to the CRB very soon.

    We are posting our proposal here and on EformulaCarNews to get feedback from those who are interested in the subject. Please read the entire post. We welcome your comments and suggestions.

    You will note that the committee has unanimously agreed on every aspect of this proposal. There are several VERY KEY elements within our proposal that we hope will convince everyone that our intentions are to make F500 a better class with more opportunity for growth in the future and that we are absolutely serious about parity between the 2 stroke and the 4 stroke engines.

    The major change to our rules porposal is that current and future 600cc MC engines will be restricted by the use of an Individual Inlet Restrictor (IIR) between the inlet manifold and the cylinder head at each inlet port. This will assure that there will be parity between the various engines used in F500. This part of the rules is the result of extensive discussions between members of the committee, several engine builders and members of the CRB.

    Another change to our rules proposal has been to allow the use of aftermarket ECU tuning modules. This is because they will be needed to properly tune the fuel map as a result of the use of the Individual Inlet Restrictors.

    To: SCCA CRB members

    Subject: A proposal to allow the use of 600cc motorcycle engines in Formula 500.

    From: The F500 motorcycle engine committee.
    Committee members
    George Dean
    Chris Huskamp
    Clint McMahan
    Dan McMahan
    Leon Mitchell
    Jim Murphy
    Jay Novak
    Jack Walbran

    Statement of Purpose:
    · To allow the use of stock production 600cc motorcycle engines for use as ALTERNATIVE ADDITIONAL engines for use in Formula 500.

    · It is the intent of this rules proposal that the current F500 Rotax 493 and non RAVE 494 2 stroke engines remain the competitive benchmark for competition adjustments to F500 when 4 stroke motorcycle engines are allowed into use in F500. To that end all motorcycle engines allowed into F500 for use, as alternate engines in F500, shall be restricted by the placement of a defined restrictor between each cylinder throttle body and each inlet port. This restrictor will be used to initially restrict the horsepower of all motorcycle engines to a TBD HP level and to limit future growth of the maximum HP of these engines. The initial size and shape of the defined restrictor shall be determined by dynamometer and track testing of a representative engine or engines. The restrictor size will be adjusted by the CRB over a period of approximately three years in order to achieve and then maintain competitive parity between the 2 stroke Rotax engines and the 4 stroke motorcycle engines.

    Background:
    As many of you are aware several members of the Formula 500 community have formed a 600cc engine rules committee to try to define a working set of rules for the use of 600cc 4 stroke motorcycle engines for use within the F500 class. We have essentially used the engine rules for FB (F1000) with several additional requirements to control engine costs and performance.

    F500, while a popular formula car class, has a relatively limited appeal to the greater formula racecar community due to many factors. These factors are concerns for many of the potential competitors in F500.
    1. The 2 stroke engine and it's associated sound
    2. Questions concerning the long term viability of the 2 stroke engine
    3. No access to new 2 stroke engines
    4. Limited access to used 2 stroke engines
    5. The CVT transmission and its associated tuning challenges, which can be a significant barrier to entry, for new competitors.
    6. No shifting due to the use of the CVT transmission

    It is very interesting that the fastest F500 cars are now as fast as the fastest F-Fords at about 1/3 the cost of a new F-Ford. You would think that this would provide for one of the most popular formula classes in the SCCA. The reality is that F500 is presently the LEAST POPULAR formula class in the SCCA and has been close to the edge of National Status several times.

    Class Rank, Class, National entries (2008)

    3, FV, 581
    4, FF, 430
    7, FE, 353
    8, FC, 337
    10, FM, 316
    11, FA, 295
    13, F5, 276

    Some competitors believe that access to snowmobile engines is a key element in the limited growth of F500. One of the reasons for this may be the relatively limited sale of snowmobiles across the US. For example:
    1. In 2007 there were 1.12 million motorcycles sold in the US
    2. In 2007 there were 79,815 snowmobiles sold in the US.
    3. That is a Ratio of over 14 to 1 for total motorcycle to snowmobile sales
    4. The estimate for the sales ratio of 600cc motorcycles to 500cc snowmobiles is at least 40 to 1 (from dealer estimates of sales)
    5. Snowmobiles are sold ONLY in northern states and this dramatically limits their availability in other parts of the country.
    6. There is NO QUESTION that there is concern about 2 strokes being legislated out of existence. Yes, there are companies that are continuing to build 2 stroke engines but the vast majority of manufacturers are now switching to much larger displacement 4 stroke engines, further restricting the future availability of 2 stroke engines.

    New, younger, competitors that we want to race in our class are not coming to F500. Direct comments are that they want “racecars that shift”. and they “do not want to work on the clutches and maintain 2 stroke engines”.

    The 600cc engine committee is confident that if 600cc motorcycle engines are approved for use as alternative engines to 2 strokes in F500, the growth of the class will be significant. When the first F500 car with a 600cc motorcycle engine was shown at the ARRC at Atlanta for show and tell, the car was BURIED BY INTEREST. At least 200 people were seriously interested in the project and the potential of the class. 2 former National Champions from other formula classes indicated that they would switch to this class if the bike engines were allowed. Numerous competitors offered deposits on the purchase of F500 cars with motorcycle engines. The interest level was amazing to say the least.

    After posting pictures of this chassis with the 600cc motorcycle engine on ApexSpeed, there have been over 10,000 views on ApexSpeed on the subjects of these engines for use in F500. The best part of all in this interest is that the VAST MAJORITY are from people who are not now involved in F500 but could certainly become new competitors. Please see this link to the many posts on the subject. [

    Again, the committee is confident that we can make the 4 strokes and the 2 strokes competitive. They have about the same HP and about the same weight, so if the cars are competitively balanced, you can race a 2 stroke if you want or you can race a 4 stroke if that is your interest.

    Also note that our efforts are intended to make CERTAIN that current F500 cars remain absolutely competitive and that the class philosophy of the absolute best value in low cost racing is maintained or even improved.

    We have based our proposed engine rules on the current F1000 (FB) rules drawn directly from the 2008 GCR. If this proposal is approved the engine rules set would be integrated into the existing Formula 500 rules.

    Proposed 600cc engine rules, this is a draft proposal and is open to changes as appropriate.

    E.15. Alternative Motorcycle Engines
    A. Mass produced (Honda, Kawasaki, Suzuki or Yamaha) water-cooled, 4 cylinder, 4-cycle motorcycle engines up to 600cc. The list of approved manufacturers may be modified by the CRB.

    B. The current F500 Rotax 493 and non RAVE 494 2 stroke engines shall be the competitive benchmark for competition adjustments to F500 when 4 stroke motorcycle engines are allowed into use in F500. To that end all motorcycle engines allowed into F500 for use, as alternate engines shall be restricted by the placement of a defined restrictor between each cylinder throttle body and each inlet port. This restrictor will be used to restrict the horsepower of all motorcycle engines to a maximum TBD HP level. The initial size and shape of the defined restrictor shall be determined by dynamometer and track testing of a representative engine or engines. The restrictor size will be adjusted by the CRB over a period of approximately three years in order to achieve and then maintain competitive parity between the 2 stroke Rotax engines and the 4 stroke motorcycle engines. (see E.15.O for additional information)

    C. All engine internals and compression ratio must remain stock. The competitor must present, on demand, an original factory manual for the engine to allow compliance verification. There shall be no modifications of any component of the engine unless specifically authorized in these rules.

    D. The stock ECU shall be used. The ECU fuel map may be changed. Devices that modify inputs to the ECU (e.g., Power Commander) may be used. Stand-alone after market ECUs are not permitted.

    E. Turbochargers and superchargers are prohibited.

    F. Carburetion or fuel injection may be used. Fuel injection if used must be stock and unmodified for the model and year of the engine that is used.

    G. The exhaust system and exhaust manifold are unrestricted, within SCCA safety regulations, except that stepped exhaust headers are not allowed.

    H. The lubrication system is unrestricted except that dry sump systems are not permitted; any oil pan and/or baffling are permitted and the use of Accusump or similar oiling assist systems is allowed.

    I. Oil coolers are unrestricted.

    J. The cooling system is unrestricted. Radiators and associated ductwork shall comply with the existing F500 bodywork rules.

    K. Replacement of the stock camshaft chain tensioner with any other chain tensioner is allowed. The replacement chain tensioner must attach directly to the engine in the original chain tensioner position. There shall be no modifications to the engine to enable the use of the replacement chain tensioner.

    L. Replacement of the standard connecting rod fasteners with alternate fasteners is allowed as long as there are no modifications to the production connecting rods. Replacement of other nuts, bolts, fasteners, and washers with common hardware items performing only the same fastening/fitting functions also is permitted as long as there are no modifications to the production parts being assembled or the production assembly.

    M. The engine head gasket must be the thickness of the OEM gasket for the year and model of the engine.

    N. Camshafts and camshaft drive mechanisms cannot be modified or adjusted in any way unless specifically authorized in these rules.

    O. The air inlet system shall have a restrictor placed between the intake manifold and the cylinder head for each cylinder intake port. This restrictor shall be made of .250” thick aluminum plate and shall have a maximum ID of XXX mm. The inlet side of the restrictors may be radiused to a maximum depth of .125”. The CRB may require adjustments to the maximum diameter of the restrictor at any time by publishing the requirements in FasTrack

    P. Self-starter: Cars shall be equipped with an on-board self-starter and an on-board power supply controlled by the driver while in a normal driving position.

    E.6. Transmission and Final Drive for motorcycle engines
    A. Rear wheel drive only is permitted.

    B. The final drive ratio is unrestricted. Internal transmission gears shall remain stock.

    C. Engines must use the sequentially shifted motorcycle transmission as supplied with the engine. Reverse gear is not required.

    D. All gear changes must be initiated and made by the driver. Only mechanical gear shifting mechanisms are allowed. This may include cables, rods, or other mechanical linkage systems. Any other assisted shifting mechanisms are specifically not allowed. This prohibition shall include electric solenoid shifters, air-shifters etc. Other similar devices are NOT permitted. Devices that allow pre-selected gear changes are also prohibited.

    E. The clutch assembly is unrestricted except that the clutch engagement system shall be operated solely by driver input and may be mechanical or hydraulic in nature. The driver’s hands or feet must manually operate the clutch and there shall be no operation of the clutch by any assisted method. There shall be no modifications to the engine/transmission to enable the use of replacement clutch components or assemblies.

    F. The use of jackshafts to transmit power from the output shaft to the rear axle is allowed.

    G. Final drive chain tensioners are allowed.

    From the F500 rules:
    E.2. Weight and Dimensions
    Minimum weight as qualified and raced, with driver, shall be 700 pounds (800 lbs. for AMW and Rotax 494 engines, 825 lbs. for Rotax 493, 835 lbs for 4 stroke 600cc motorcycle engines.
    Wheelbase: Maximum 80”
    Overall Length: Minimum 110”
    Maximum 150”
    Overall Width: Minimum 50”
    Maximum 55”

    Thanks ... Jay Novak
    F500 since 1984
    Last edited by Jnovak; 02.08.09 at 4:49 PM.
    Thanks ... Jay Novak
    313-445-4047
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    with a special thanks to every SCCA worker (NONE OF US WOULD RACE WITHOUT THE WORKERS)

  2. #2
    Junior Member Charlie_S's Avatar
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    Hi Jay,

    There are logical flaws in your proposal that others will argue more eloquently than I. Is your 835 lbs based on the fact that this is about as light as you can get w/the bike motor set-up and driver, some sort of competitive adjustment or just a bargaining chip? We had to add 50 lbs just to run the 493, initially.

    Each engine change has resulted in the new engine dominating and obsoleting the old, though the 494 is still a viable option.

    Don't you think you might get a little more acceptance from some those w/a 2-stroke-CVT investment if you bumped the weight up? A lot?

    Good Luck and See You Later,

    Charlie and Marilyn Schlismann
    #71 MIDIV

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    Thank you to all the members of the F500 motorcycle engine committee for all of your time and effort to draft this proposal.

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    Contributing Member Jnovak's Avatar
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    Thanks for your input Charlie. You may be right on this, however the consensus was that we did not want to totally over burden the cars with weight and the inlet restrictors.

    Your input is exactly why we are posting this on the 2 forums. We truely want the input of those not on the committee, particularly those who are current F500 competitors. If there is a lot of interest in this issue I am sure the committee will re-evaluate the weight requirement before we send the proposal to the CRB.

    Thanks ... Jay Novak
    Thanks ... Jay Novak
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    Contributing Member formulasuper's Avatar
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    Default Finally!

    It sure is good to see this all taking place, and only about 14 years after we first proposed it!
    Scott Woodruff
    83 RT5 Ralt/Scooteria Suzuki Formula S

    (former) F440/F5/FF/FC/FA
    65 FFR Cobra Roadster 4.6 DOHC

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    Senior Member lancer360's Avatar
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    Thanks to all the members who have spent so much of their time putting this together! I like the rules the way they are with the IIR diameter to be determined after on track testing.
    Chris Ross
    09 NovaKBS F600 #36 Powered by '09 600 Suzuki GSX-R
    "If all else fails, immortality can always be assured by spectacular error." John Kenneth Galbraith

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    As a very interested observer of this process and having spoken with F500 entrants about their cars, it appears to me that the brakes, in particular, are already overburdend on these cars. Why not make the new 600 cc motors race in one of the lower weight catagories and limit the performance by IIR only?
    Hope to join your group someday when my F1000 days are over!

    Greg Lindahl

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    Quote Originally Posted by ReynardF1000 View Post
    As a very interested observer of this process and having spoken with F500 entrants about their cars, it appears to me that the brakes, in particular, are already overburdend on these cars. Why not make the new 600 cc motors race in one of the lower weight catagories and limit the performance by IIR only?
    Hope to join your group someday when my F1000 days are over!

    Greg Lindahl
    Hi Greg, My chassis will come with big enough brakes. I also plan on making adapters to fit other current f500 cars as a brake upgrade.

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    Default F-600 rules

    I haven’t had the time to really read through the rules and give them the attention they deserve but below are some comments and questions after my first read. By the way you’ve really put a lot of effort into these rules so far. Thanks for your dedication to the class.

    E.15. Alternative Motorcycle Engines
    B. The current F500 Rotax 493 and non RAVE 494 2 stroke engines shall be the competitive benchmark for competition adjustments to F500 when 4 stroke motorcycle engines are allowed into use in F500. To that end all motorcycle engines allowed into F500 for use, as alternate engines shall be restricted by the placement of a defined restrictor between each cylinder throttle body and each inlet port. This restrictor will be used to restrict the horsepower of all motorcycle engines to a maximum TBD HP level. The initial size and shape of the defined restrictor shall be determined by dynamometer and track testing of a representative engine or engines. The restrictor size will be adjusted by the CRB over a period of approximately three years in order to achieve and then maintain competitive parity between the 2 stroke Rotax engines and the 4 stroke motorcycle engines. (see E.15.O for additional information)
    Some questions:
    1. We’re currently awaiting dyno test results for the Rotax 494 RAVE motor. How will this motor be incorporated into the bench mark comparison list? Assuming the Rave will have the same HP as the non-RAVE/493 can we include it in the list after the test is completed and verify the numbers?
    2. In the above rule are you saying the 600cc motor will be track tested WITHOUT a restrictor and IF it needs one then it will be in the form of an Individual Inlet Restrictor (IIR)? [I prefer to call it a Fuel Air Intake Restrictor (FAIR) adjustment and would like to see them limited to a 0.5 inch diameter (just kidding)].
    3. The TBD restricted HP number for 600cc motors will presumably be comparable to the Rotax motors. Where will the HP numbers be measured? By this I mean the motorcycle motors are typically measured at either the counter-shaft or rear–wheel and the Rotax from the crankshaft. I would suggest measuring the 600cc motor at the countershaft and compare that to the crankshaft of the Rotax motor - with appropriate correction for the gear reduction.

    F. Carburetion or fuel injection may be used. Fuel injection if used must be stock and unmodified for the model and year of the engine that is used.
    1. What about carburetors?

    O. The air inlet system shall have a restrictor placed between the intake manifold and the cylinder head for each cylinder intake port. This restrictor shall be made of .250” thick aluminum plate and shall have a maximum ID of XXX mm. The inlet side of the restrictors may be radiused to a maximum depth of .125”. The CRB may require adjustments to the maximum diameter of the restrictor at any time by publishing the requirements in FasTrack.
    1. What about the outlet side of the restrictor? Any dimensions/restrictions?
    2. Should we consider a single source for the agreed upon restrictor? Everybody gets them from the same source.

    D. All gear changes must be initiated and made by the driver. Only mechanical gear shifting mechanisms are allowed. This may include cables, rods, or other mechanical linkage systems. Any other assisted shifting mechanisms are specifically not allowed. This prohibition shall include electric solenoid shifters, air-shifters etc. Other similar devices are NOT permitted. Devices that allow pre-selected gear changes are also prohibited.
    1. Will no-lift-shift mechanisms be allowed?

    From the F500 rules:
    E.2. Weight and Dimensions
    Minimum weight as qualified and raced, with driver, shall be 700 pounds (800 lbs. for AMW and Rotax 494 engines, 825 lbs. for Rotax 493, 835 lbs for 4 stroke 600cc motorcycle engines.
    I’m not sure any of these weights are realistic for most people in the class. However, I think the 600cc motor should have the same restriction placed upon them the Rotax 493 did when introduced – 850 lbs.

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    Contributing Member Jnovak's Avatar
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    Ted, very good questions. Please see my comments below:

    E.15. Alternative Motorcycle Engines
    B. The current F500 Rotax 493 and non RAVE 494 2 stroke engines shall be the competitive benchmark for competition adjustments to F500 when 4 stroke motorcycle engines are allowed into use in F500. To that end all motorcycle engines allowed into F500 for use, as alternate engines shall be restricted by the placement of a defined restrictor between each cylinder throttle body and each inlet port. This restrictor will be used to restrict the horsepower of all motorcycle engines to a maximum TBD HP level. The initial size and shape of the defined restrictor shall be determined by dynamometer and track testing of a representative engine or engines. The restrictor size will be adjusted by the CRB over a period of approximately three years in order to achieve and then maintain competitive parity between the 2 stroke Rotax engines and the 4 stroke motorcycle engines. (see E.15.O for additional information)
    Some questions:
    1. We’re currently awaiting dyno test results for the Rotax 494 RAVE motor. How will this motor be incorporated into the bench mark comparison list? Assuming the Rave will have the same HP as the non-RAVE/493 can we include it in the list after the test is completed and verify the numbers? If it is the same, I personally do not see any reason why the Rave motor should not be included. However the decision is COMPLETLY UP TO THE CRB & THE BOD.

    2. In the above rule are you saying the 600cc motor will be track tested WITHOUT a restrictor and IF it needs one then it will be in the form of an Individual Inlet Restrictor (IIR)? [I prefer to call it a Fuel Air Intake Restrictor (FAIR) adjustment and would like to see them limited to a 0.5 inch diameter (just kidding)]. The CRB has said they will REQUIRE an intake restrictor, regardless of the HP level. They want this to eliminate year to year HP growth of the 600cc engines. We will test without to get a comparison.

    3. The TBD restricted HP number for 600cc motors will presumably be comparable to the Rotax motors. Where will the HP numbers be measured? By this I mean the motorcycle motors are typically measured at either the counter-shaft or rear–wheel and the Rotax from the crankshaft. I would suggest measuring the 600cc motor at the countershaft and compare that to the crankshaft of the Rotax motor - with appropriate correction for the gear reduction. That is the intent, HP at the countershaft for the 600 & at the crank for the Rotax. However this is just a start & track testing and racing will be used to make sure things are meaningful. There are plenty of additional variables that cannot be accounted for on the dyno, for instance, the CVT has extremely good acceleration due to constantly being at peak power if properly setup. There is also no time lost in shifting a CVT where there is lost time at EVERY SHIFT with a gearbox. The CRB plans to start the 600 engines with less HP than the Rotax engines & then adjust upwards as needed. Track testing will include restrictors of several sizes as well as no ristrictors too for comparitive purposes.

    F. Carburetion or fuel injection may be used. Fuel injection if used must be stock and unmodified for the model and year of the engine that is used.
    1. What about carburetors? Carbs are legal & will still need Intake restrictors

    O. The air inlet system shall have a restrictor placed between the intake manifold and the cylinder head for each cylinder intake port. This restrictor shall be made of .250” thick aluminum plate and shall have a maximum ID of XXX mm. The inlet side of the restrictors may be radiused to a maximum depth of .125”. The CRB may require adjustments to the maximum diameter of the restrictor at any time by publishing the requirements in FasTrack.
    1. What about the outlet side of the restrictor? Any dimensions/restrictions? We think the rule is adequate in that it defines a MAXIMUM DIAMETER with a radius only on the inlet side. If the CRB does not like the wording they will revise as they think necessary.

    2. Should we consider a single source for the agreed upon restrictor? Everybody gets them from the same source. That would be the best solution IMHO.

    D. All gear changes must be initiated and made by the driver. Only mechanical gear shifting mechanisms are allowed. This may include cables, rods, or other mechanical linkage systems. Any other assisted shifting mechanisms are specifically not allowed. This prohibition shall include electric solenoid shifters, air-shifters etc. Other similar devices are NOT permitted. Devices that allow pre-selected gear changes are also prohibited.
    1. Will no-lift-shift mechanisms be allowed? How do you define a no lift shift? That can be done right now without any add on stuff. I think that you may be refering to an ignition controller, if this is what you mean then no that would not be legal. Perhaps a micro switch on the shifter might be legal. This needs to be sorted out.

    From the F500 rules:
    E.2. Weight and Dimensions
    Minimum weight as qualified and raced, with driver, shall be 700 pounds (800 lbs. for AMW and Rotax 494 engines, 825 lbs. for Rotax 493, 835 lbs for 4 stroke 600cc motorcycle engines.
    I’m not sure any of these weights are realistic for most people in the class. However, I think the 600cc motor should have the same restriction placed upon them the Rotax 493 did when introduced – 850 lbs.[/quote] Weight request noted. You are number 2. I think that with the restrictions the CRB has in mind the 600cc car will be at least 2 seconds off the pace of the BEST F500 cars with Rotax power.

    Thanks ... Jay Novak
    Last edited by Jnovak; 02.07.09 at 8:05 PM.
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    Are we thinking that all 600MC engines will receive the same size restrictor?


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    Contributing Member Jnovak's Avatar
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    Quote Originally Posted by Quickshoe View Post
    Are we thinking that all 600MC engines will receive the same size restrictor?

    Basically the answer is YES. This is very similar in function to an SIR (Single Inlet Restrictor) in that it limits the total airflow into the engine, thus limiting the HP to a maximum that the airflow can support. Even modified engines will not make much if any more power. This should work really well for stock engines.

    There actually has been a lot of work done with this type of restrictor. They are used in some "stock restricted" classes for 600cc mini sprints. The best part of this type of restrictor is that they can use the stock or slightly adjusted ECU.

    A single inlet restrictor also does a really good job at keeping power to a very close range. The downside of an SIR is that the stock ECU simply will not work. The FSAE guys use a small SIR to keep their 600cc bike engines around 80+ hp

    Thanks ... Jay Novak
    F500 since 1984
    Thanks ... Jay Novak
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    Senior Member rickjohnson356's Avatar
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    Default jumping the gun a little??

    So far as I know, only the ATL region has specifically allowed the 600 MC class. The first event where these can play is in a couple of weeks at Rd Atl regional. (A SARRC points event.

    Shouldn't you get some experience with the way the cars run and where they stand competitively before formalizing rules about weight, SIR size, etc? Just an outsider's observation.

    However, I agree about posting the tentative rules for discussion purpose, just not proposal purposes.

    Looks like a bunch of guys in the know have thought the concept out pretty thoroughly. Any idea of how many folks are seriously considering either building one or buying one from Jay? It might be good to have a couple on the track in a competitive event, not just testing, to see where the new configuration fits in the class.

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    the northwest region has approved the f600s to run for the evaluation period thanks to rick for getting that done.the rules are just a starting point.as jay said on eformulacarnews.the 600s will be 2 seconds off the pace of a front running f500 with the current rules.so i assume they will adjust up to be competitive.

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    Contributing Member Jnovak's Avatar
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    Please read the rules proposal carefully, there is not a defined specification for the Individual Inlet Restrictors yet. The definition will be the result of testing over the next season.

    Right now there are 6 cars being built with 600 engines in them (I think). I suspect that we will have at least 10 being built before too long.

    I have had numerous requests to build new cars but I am not prepared to do that at this time as I have other business commitments.

    Thanks ... Jay Novak
    Thanks ... Jay Novak
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    Quote Originally Posted by ReynardF1000 View Post
    As a very interested observer of this process and having spoken with F500 entrants about their cars, it appears to me that the brakes, in particular, are already overburdend on these cars. Why not make the new 600 cc motors race in one of the lower weight catagories and limit the performance by IIR only?
    Hope to join your group someday when my F1000 days are over!

    Greg Lindahl
    Greg,
    First, Rusty Cook ran his F500 for many years at over 900 pounds w/driver and was very competitive.
    Second, the top speed for both drivetrains will be about the same and bigger brake swept area can be installed if need be.
    Remember that weight affects ALL aspects of racing while IIR's ONLY affect acceleration and top speed.

    Jim
    Been messing with these cars since 1982

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    Quote Originally Posted by rickjohnson356 View Post
    So far as I know, only the ATL region has specifically allowed the 600 MC class. The first event where these can play is in a couple of weeks at Rd Atl regional. (A SARRC points event.

    Shouldn't you get some experience with the way the cars run and where they stand competitively before formalizing rules about weight, SIR size, etc? Just an outsider's observation.

    However, I agree about posting the tentative rules for discussion purpose, just not proposal purposes.

    Looks like a bunch of guys in the know have thought the concept out pretty thoroughly. Any idea of how many folks are seriously considering either building one or buying one from Jay? It might be good to have a couple on the track in a competitive event, not just testing, to see where the new configuration fits in the class.
    The proposal will be submitted to the CRB/BOD early enough so that, if approved, it will be effective for 2010. For 2009, we will be evaluating through on-track performance both what weight to run at and what size IIR's to use for 2010.
    In the Atlanta area, Dan and Clint McMahan are converting Clint's black F5 and Dan's original Dolphin cars over to F6's. It will be nip and tuck if they can get one ready for the February regional but they feel comfortable that they can get both ready for the Friday test day (only) of the March national. Jay (in Michigan) is hoping to have his ready for the February regional as well but it is a day-to-day situation with him. They will find other regional races to run at for the remainder of this season. Several drivers have already asked Dan & Clint to convert their cars as well - and they want it done right now. This is going to make for a very busy season for them but will hurt the national F5 participation in the SEDIV in 2009 as several other SEDIV F5 drivers have stated that they are not running this year due to the poor economy.

    Jim

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    Contributing Member Jnovak's Avatar
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    The proposal has been sent to the CRB. See the proposal at the top of this post.

    Thanks ... jay Novak
    Thanks ... Jay Novak
    313-445-4047
    On my 54th year as an SCCA member
    with a special thanks to every SCCA worker (NONE OF US WOULD RACE WITHOUT THE WORKERS)

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