New F600 rules proposal

[Jnovak]

As many of you are aware our original F600 proposal to allow for the use of 600cc MC engines for use as alternative engines in F500 was not approved by the CRB, The CRB recommended that a new seperate class be started called F600.

As a result of this decision the F600 MC engine committee has decided to propose a new stand alone rules set of the new F600 class. After MUCH discussion and negotiation the F600 Committee proposed a new set of rules to the CRB and it was just posted today.

Here is the link to the CRB minutes so that you can review the proposal. Our goal was to create a new low cost open wheel class powered by true production 600cc motorcycle engines. We wanted to make certain that this class would allow for both converted F500 cars as well as newly designed cars to compete on an equal footing.

Please take a look at our new rules proposal and make comment that you think appropriate. If we can get this approved this class will grow very quickly to easily a top 10 class in the club within 5 year.

Here is the link to the proposal:

http://www.scca.com/assets/Prelimina...tes_v2b%20.pdf and here: http://www.scca.com/assets/Preliminary_December_TB.pdf

Thanks ... Jay Novak

[Marshall Mauney]

Jay -

Why the allowance for full spring/shock suspension? Isn't that a potential cost issue?

[Jnovak]

Jay -

Why the allowance for full spring/shock suspension? Isn't that a potential cost issue?

Yes, there are cost implications Marshall, however the way the rules are structured they are not needed to be competitive.

One of the reasons why we want to have shocks is to allow those who do not want to deal with the rubber suspension but want something more mainstream that they can work with.

The other main reason for the shock/spring option is for the future growth of the class. We want F600 to be a real training ground where young drivers can get some real sorting and tuning experience in a very low cost open wheel car and the coil-overs will offer that.

We think that the net cost differences between rubber suspension and coil-over shocks will be about $1500. Not for everone and we are confident that the rubber suspended cars with a 50lb weight advantage will be very equal to the coil-over cars.

We should have our 1st prototype with rubber suspension up and running by spring.

Thanks ... Jay Novak

[Daryl DeArman]

My first reaction to the shock/spring deal was "darn....no thanks".....but then the only extent to which the class is being marketed to me is as a potential owner should the class take off. I'm mid-40's, not interested in moving on to other higher dollar formulae. I'd think the ruleset should be geared towards other folks and if I happen to want to join in, I will.

Then I saw the mandate of a solid rear axle, no independent rear suspension allowed and a 50#weight break/penalty (depending on perspective)....okay this might be an acceptable work around.

Would the class even consider a shock claimer (say $500 on a shock/spring combo) to disuade folks from running $6K worth of shocks on their entry level car? If that's a deal breaker, fine. Just throwing it out there as there seems to be some desire to limit the cost of the shocks by only allowing them to be 2 way externaly adjustable.

[Mark_Silverberg]

I find this all very interesting. As a present vintage racer who would like to run SCCA at some point in my career a no wings / modern engine class holds a lot of appeal. I had some reservations previously as I was never a huge fan of the rubber suspension cars. I know Jay has done a lot of work with them and knows them well - but I am just more comfortable with conventional shocks and springs. The extra weight of the steel spring car will not be an issue for larger drivers. These specifications seem like they will make for a car which is extremely fun to drive and very tuneable. While is easy to think about the big dollar shocks there are many less expensive options which would probably work quite well.

I think this class could hold a lot of appeal for some one wanting to move from karting but not into a class with wings.

[Jnovak]

Would the class even consider a shock claimer (say $500 on a shock/spring combo) to disuade folks from running $6K worth of shocks on their entry level car? If that's a deal breaker, fine. Just throwing it out there as there seems to be some desire to limit the cost of the shocks by only allowing them to be 2 way externaly adjustable.

Daryl, look closely at the shock rule. The shocks are very limited to a single body (no external canisters) and only 2 adjustments, 1 compression and 1 rebound. This will essentially prevent the use of the very high $$ triple of quad adjustable shocks. I have 2 quotes from shock manufaturers who will supply a shock to those rules for under $500 per shock. This will be very effective at controlling shock costs. Also consider what a rubber sprng cannister costs from the major F500 builders, they are about $200 each. That means that the cost differential for the shock option is only about $1500 or less. Not a bad deal IMHO.

We will be building 2 cars this winter, 1 with rubber springing and 1 with shocks.

Thanks ... Jay Novak

[Daryl DeArman]

Jay,

I appreciate all the efforts. I was just tossing it out there. I know that one can get a no-frills very good shock for $500, what I hope proves out over time that a shock like that is good enough....or ideally that the no shock/coil spring package proves out to be the hot ticket.

If the shocks and bigger tire / bigger car bring more people to the party, then great!

[nulrich]

I very much like the idea of a low-cost formula car based on 600 cc motorcycle engines. I think it should be possible to build a very inexpensive car with great performance.

I wouldn't want to design a car with rubber suspension, not because it couldn't be made to perform well, but because I couldn't use my current understanding of suspension design. Also, you can spend a lot of money developing trick elastomeric bushings (look to other series and their "bump rubbers") but the resulting knowledge isn't applicable to other formula cars.

Going to 13 inch wheels is a very positive step, but wouldn't a size common to either FF (5.5 inch width) or FC (6 or 8 inch width) makes more sense?

One way to limit damper costs is to require homologation of all dampers, and only homologate dampers that retail for $500 or less.

I may have missed it, but is there a prohibition against streamline tubing? I would suggest that as a good way to limit suspension costs.

Nathan

[Daryl DeArman]

Quite possibly the damper deal will be a non-issue, smooth pavement track conditions don't change that much other than wet/dry. I am tainted by my CDCRA (open wheel dirt track series on a spec tire) experience. Dirt track conditions change from one extreme to another. Shocks were a major part of the equation in the early days of the series. They tried to limit the costs by mandating a non-externally adjustable shock---what ended up happening is the well funded and fast teams had 5 sets of shocks all valved for different conditions. Didn't save anybody any money who wanted to run up front.

[Jnovak]

I very much like the idea of a low-cost formula car based on 600 cc motorcycle engines. I think it should be possible to build a very inexpensive car with great performance.

I wouldn't want to design a car with rubber suspension, not because it couldn't be made to perform well, but because I couldn't use my current understanding of suspension design. Also, you can spend a lot of money developing trick elastomeric bushings (look to other series and their "bump rubbers") but the resulting knowledge isn't applicable to other formula cars.

Going to 13 inch wheels is a very positive step, but wouldn't a size common to either FF (5.5 inch width) or FC (6 or 8 inch width) makes more sense?

One way to limit damper costs is to require homologation of all dampers, and only homologate dampers that retail for $500 or less.

I may have missed it, but is there a prohibition against streamline tubing? I would suggest that as a good way to limit suspension costs.

Nathan

Nathan, your idea about not using aero tubing has been discussed within our F600 committee before and the only problem with this rule is that all the current cars & future conversion cars all have aero tube front control arms. This would then require that all of those cars replace their control arms.
For many years we have been making our own "aero" tube for very low cost control arms. We have machined a 2 piece die that compresses 2 different sizes of round DOM tubing. It works great and we can make enough tubing for a complete set of control arms in about 15 minutes.

I like your idea about homologating shocks, I am not sure that the SCCA would go for it though as it is more work for everyone to keep track of things. Tough to do with a nearly all volunteer staff.

The 13" wheel size was really defined by talking to a couple of tire engineers from Hoosier and Goodyear. The 5.5" wheel width of the FF cars requires a cantilever tire to work properly and these are expensive tires. Both Hoosier and Goodyear currently make low cost slicks that fit on a 7" rim. These tires are what they think are most appropriate for the weight of the F600 cars. If much bigger tires are used the cars will have grip problems due to low tire temps. There are plenty of wheel manufacturers who will make a 7" rim for essentially the same cost as a 6 or an 8. Do not be surprised if these cars use a 7" wide rim (13" wheel) on both ends of the car.

Thanks ... Jay novak

[nulrich]

That all makes sense, Jay. Thanks for explaining!

I have to admit to a prejudice against F440/F500 cars based solely on the noise they make (I know it's a stupid reason, and I don't mean to offend anyone). I'm guessing the F600 cars sound great.

Nathan

[starkejt]

I have to say, the two major turnoffs for me (noise and rubber suspension) are being addressed. No offense, but I wouldn't exactly shed a tear if this idea took off and obsoleted the snowmobiles.

[RussMcB]

The motorcycle engines scream! (in a good way). And the 6 speed transmission is way more attractive that the F500 setup, too.

[nulrich]

I have a few more questions, which hopefully aren't too obvious.

Why the maximum wheelbase? I think designers will converge on the best solution if you don't put in a limitation. I understand the maximum length requirement.

Why limit springs to steel coils? Torsion bars and even leaf springs, especially if integrated into other parts or used with a solid rear axle, can be less expensive and lighter.

I'm not familiar with the rear camber situation on current F500 cars. Is the intent to allow negative camber at the rear (through the clever methods used in other types of cars) or to prevent that completely?

I don't completely understand the bodywork regulations, especially the sidepods. Is the intent that sidepods have completely vertical sides, or can they be contoured from the lower edge to the upper edge? I can imagine all kinds of interesting shapes that might help produce downforce, so it might be a good idea to clarify that through a diagram or rules language.

Do you really mean "longitudinal section" for the 1 inch deviation from horizontal?

Also, being unfamiliar with the class, the term "sportscar nose" doesn't necessarily imply much restriction on the shape. How is the shape of the bodywork in front of the front wheels constrained?

Thanks,

Nathan

[SEComposites]

I think you should look at a year cap for motors as well. This can always be updated in the future. Also is the cost increased that much more to have IRS? You can still outlaw diffs of course.

[R. Pare]

Daryl, look closely at the shock rule. The shocks are very limited to a single body (no external canisters) and only 2 adjustments, 1 compression and 1 rebound. This will essentially prevent the use of the very high $$ triple of quad adjustable shocks. I have 2 quotes from shock manufacturers who will supply a shock to those rules for under $500 per shock. This will be very effective at controlling shock costs.

Ever look at and price out the Penske 2000's? They fit your description exactly, and are ex-F1 shocks with the premium price that goes with it. Same for the Ohlins TTX - it can be had with just 2 external adjusters as well.

The problem, as always, with thinking that limiting features on shocks is that it never works as intended - once someone finds out a way around the limitations, the costs escalate. Case in point: years ago one of the regions restricted Club Ford to steel bodied shock. We started making steel replacement bodies for the guys who already had Penske 8760s. Damned site more expensive that if the rules had remained open, and the rule was soon dropped

[Daryl DeArman]

I have to admit to a prejudice against F440/F500 cars based solely on the noise they make.

That's music to many. Personally, I love the sound of a 2 stroke IF the rpms aren't stuck in the same narrow rpm band. I like the smell too, especially if using Blendzall but I digress.

If shocks are what it takes to attract the masses, so be it. I believe the only way you contain the costs there are to leave them off the car

Thanks again to the entire committee and the early pioneers!!

[starkejt]

The external canister ban doesn't exclude the Ohlins TTX40, which are $10k for a car set. Sure they are normally quad adjustable, but perma-fixing 2 of the adjusters gets around that as Richard said. Perhaps exclude twin-tube or through-shaft dampers?

[Ananth K]

Why can a spec shock and valve stack not be mandated? A non-adjustable steel bodied shock for this application can be had from Bilstein today for under $90.

[Hardingfv32]

Jay

When you build a new coil over car, do you anticipate have to do anything to the suspension geometry? Will it be as simple as integrating the coil overs into your present rocker system?

Brian

[Jnovak]

I have a few more questions, which hopefully aren't too obvious.

Why the maximum wheelbase? I think designers will converge on the best solution if you don't put in a limitation. I understand the maximum length requirement.

Why limit springs to steel coils? Torsion bars and even leaf springs, especially if integrated into other parts or used with a solid rear axle, can be less expensive and lighter.

I'm not familiar with the rear camber situation on current F500 cars. Is the intent to allow negative camber at the rear (through the clever methods used in other types of cars) or to prevent that completely?

I don't completely understand the bodywork regulations, especially the sidepods. Is the intent that sidepods have completely vertical sides, or can they be contoured from the lower edge to the upper edge? I can imagine all kinds of interesting shapes that might help produce downforce, so it might be a good idea to clarify that through a diagram or rules language.

Do you really mean "longitudinal section" for the 1 inch deviation from horizontal?

Also, being unfamiliar with the class, the term "sportscar nose" doesn't necessarily imply much restriction on the shape. How is the shape of the bodywork in front of the front wheels constrained?

Thanks,

Nathan

Glad to see that you are interested in F600 Nathan. First let's talk intent and if the intent of the rules is not adequately defined then we will certainly rewrite them to make certain that that the intent of the rules are clearly defined.

The bottom part of the car from the body rule:

[FONT=Times New Roman][FONT=Univers]Bodywork behind the front wheels and forward of the rear wheels shall extend to within one (1) inch of a line connecting the outer edges of the front and rear wheels. In a horizontal plane, it shall begin within 2.5 inches of the rear-most part of the tire in the completely turned position and extend to within 4.5 inches of the front of the rear tire. The sidepod(s) shall be continuous from the outside edge of the main [/FONT][FONT=Univers]bodywork, at a minimum height of nine (9) inches, maximum twelve (12) inches measured from the bottom plane of the car. The sidepod(s) shall be closed across the front except for air duct openings to heat exchanger(s), but ALL ducted air shall pass through those exchanger(s). The sidepod(s) may be open to the rear. Sidepod(s) is (are) intended to restrict wheel entanglement between cars. The purpose of these rules is to minimize the use of “ground effects” to achieve aerodynamic downforce on the vehicle. Thus, for full width of the body between the front and rear axles, the lower surface (surface licked by the airstream) shall not exceed 2.54cm (1 inch) deviation from the horizontal in any longitudinal section through that surface. (This is not to be interpreted as requiring a floor pan beneath the engine or rear axle.) The [/FONT][FONT=Univers]bodywork shall not extend below the surface the chassis floor to the rear of the front axle. Seat bucket or other protrusions shall not circumvent this rule. It is not permitted to duct air through any part of the [/FONT][FONT=Univers]bodywork for the purpose of providing aerodynamic downforce on the car. Wings are prohibited. [/FONT][/FONT][FONT=Univers][FONT=Times New Roman]Rear diffusers are permitted. The maximum width of the diffuser is limited to a dimension that is narrower that the distance between the insides of the rear tires.[/FONT][/FONT]

The obvious intent of the bottom of the car rule is to make certain that these cars have completely flat bottom between the wheelbase centerlines and for the full width of the car with a maximum deviation of 1" from the lowest spot on the bottom of the chassis. This does not mean that you cannot shape the bottom of the car, it simply means that there shall not be any deviation from the lowest point to the highest point that is greater than 1" in a longitudinal or a lateral direction. So much for that. I will ask the CRB if it is necessary to reword this section of the rule to prevent any other interpretation of this rule. I am certain that they will do that if needed.

Maximum wheelbase: again this is to control costs. Someone will always be looking for an opportunity to improve the dynamics of these cars. Constant design development costs big bucks that always get passed on to the customer to the detriment of the class. So setting a maximum wheelbase that you can actually package a race car in will help to control those costs and to allow older cars to remain competitive for a longer time. FV and F500 have had maximum wheelbases for a very long time with no problems.

Rear camber: It is clearly intended to not allow for any camber adjustments at all. Here is the rule:

[FONT=Times New Roman]A. The[FONT=Univers] r[/FONT]ear driving axle shall be of solid or tubular steel or high strength aluminum alloy. The axle shall be a one piece live axle, driving both rear wheels. Trailing arms are allowed. Differentials and/or slip joints are not permitted. Spacers for drive components are permitted.[FONT=Univers] The intent of this subsection is to eliminate independent rear suspension of any type, or provision for lateral movement of the axle shaft to facilitate independent‑type suspension.[/FONT][/FONT]

Pretty simple in our opinion. Many builder have used light weight steel tubing to allow for flex in the axles but this has not proven to be an advantage. Our current cars use a 50mm x 4mm wall steel tube. This works just fine. Others use other sizes. There was one builder about 20 years ago who tried a camber adjustable hub on each side and that was ruled illegal immediately.

Additionally depending on the axle length, bearing placement etc, the tire show anywhere from 10 deg to 20 deg temperature difference indicating that they have dynamic negative camber.


Side pod shapes: Pretty much everyone uses relatively flat side that MUST be within 1" of the outside of the tire. While this 1" is allowed most do not attempt to shape the sides of the sidepods even though this is a definite side for advantage in yaw. Side pod must also have a minimum height of 9" from the bottom of the car and a maximum heigh of 12". They must also be continuous with no breaks in the surfaces between the outer side and the cockpit.

Sports Car nose rule:
[FONT=Times New Roman][FONT=Univers]Sports car noses are recommended provided they do not extend beyond the outside edge of the front [/FONT][FONT=Univers]tires, do not stand taller than the top of the front [/FONT][FONT=Univers]tires, and their rearward most portion does not extend beyond an imaginary line drawn from the center of the front wheel, forty (40) degrees forward from vertical.[/FONT][/FONT]
There is a lot of latitude in the rule as written except that the rule also states at the end of the body section that wings are prohibited. This will prevent any type of nose shape that is a wing. This does not mean that you cannot make front Df with a Sports Car nose it simply means that wing shapes are prohibited.

Nathan we would also welcome your input as to the clarity of the rules. Now is the time for this sort of thing to happen, not a year from now when many people are building cars. So do not hesitate to contact me or any other person on the F600 committee. Another contact might be Dave Gomberg of the CRB, Dave has been very helpfull with the rules.

Thanks ... Jay Novak

[Jnovak]

Ever look at and price out the Penske 2000's? They fit your description exactly, and are ex-F1 shocks with the premium price that goes with it. Same for the Ohlins TTX - it can be had with just 2 external adjusters as well.

The problem, as always, with thinking that limiting features on shocks is that it never works as intended - once someone finds out a way around the limitations, the costs escalate. Case in point: years ago one of the regions restricted Club Ford to steel bodied shock. We started making steel replacement bodies for the guys who already had Penske 8760s. Damned site more expensive that if the rules had remained open, and the rule was soon dropped

Thanks Richard, obviously we are very concerned with this particular issue. There has been much discussion within our committee on how to best control this particular issue. Penske makes a very functional shock that retails for about $500. Single body, double adjustable, floating piston, aluminum or steel body. That is the target we are looking for. The question is how to best achieve this. This sort of shock would easily do the job on an approximate 900 lb car with low unsprung weight.

How to control the costs is obviously the major issue.

Your ideas & thoughts are very welcome.

Thanks ... Jay Novak

[Jnovak]

Jay

When you build a new coil over car, do you anticipate have to do anything to the suspension geometry? Will it be as simple as integrating the coil overs into your present rocker system?

Brian

The only differece will be in the rockers and pushrods. I have already modeled both the rubber suspension as well as a shock with a 1:1 ratio. Of course the rockers are very different.

Thanks ... Jay Novak

[Jnovak]

Why can a spec shock and valve stack not be mandated? A non-adjustable steel bodied shock for this application can be had from Bilstein today for under $90.

Ananth there are a few of problems with a non adjustable spec shock.

1. The new driver never gets to learn how to setup the shocks on a car. We think this is critical to an entry level open wheel class.

2. With a spec shock then everyone will have to play with tuning the damping with rockers and motion ratios. In the long run this does not meet our targets of having a tunable low cost open wheel class.

3. There is NO WAY for the SCCA tech people to measure or control a spec shock. This means that "someone" will build very high $$$ shocks that look exactly like the "spec shock"

There may be other solutions and we are open to ideas.

Thanks Jay Novak

[Jnovak]

Of course we welcome comments about how to clean up the rules. However the most important issue is that the F600 rules proposal must be approved.

The rules have been written by many people who have given this a TON of thought and discussion. The current rules proposal is just that a proposal for the CRB & the BOD to approve or not. I think that the only things that might change are slight rewordings to clarify certain issues.

We (the F600 committee) are interested in getting this proposal approved, that is the number 1 priority. I get the very distinct impression that there is a LOT of support for the F600 concept. We simply cannot go on trying to change every small detail or it will NEVER BE DONE.

Once the class is approved the CRB can make performance adjustments or define a shock supplier etc.

The CRB will give us a month or so to let them know whether we want F600 to exist or not. Send in your letter to the CRB or alternatively talk about it forever.

Thanks ... Jay Novak

[Purple Frog]

Jay,

I really like the idea of a new rule set. As you know, a few years ago you and I spoke about lengthing the wheelbase to create better handling and safer cars. You didn't want to do it then to prevent disenfranching the F5 cars. That is not a problem at this juncture. I am not sure a maximum is needed. Let that shake out in the engineering.

I see this class as being a great "little Sister" to F1000. Much like FF is the "no wings" little brother to FC, this class could be the "no wings" little sister to FB. With that said, I truly believe you need to dump the straight axle. Go with IRS and a diff. FB and DSR have already broken the ice. It will teach the people in this class how to set up for mechanical grip in real race cars. And it is a knowledge that can be carried up into other classes. Straight axles are for karts and sprint cars. If you are writing new rules, go all the way. Drop the straight axle!

I see the sportscar nose, and wide sides as a great benefit to safety.

[Will Velkoff]

I see this class as being a great "little Sister" to F1000. Much like FF is the "no wings" little brother to FC, this class could be the "no wings" little sister to FB. With that said, I truly believe you need to dump the straight axle. Go with IRS and a diff. FB and DSR have already broken the ice. It will teach the people in this class how to set up for mechanical grip in real race cars. And it is a knowledge that can be carried up into other classes. Straight axles are for karts and sprint cars. If you are writing new rules, go all the way. Drop the straight axle!

Couldn't agree more, the class will be MUCH more appealing in my opinion if you allow differentials/IRS in the rear.

Also have you thought about ex-Formula SAE cars being a good candidate for a "new" build?

[Brands]

As a class in its own righ, personally I don't think the motors should run with any kind of inlet restriction. I also think an open diff and IRS would be a good way to go if the class is to attract younger racers. I'd prefer a diff over shocks if I'm honest (just!).

[Marty Nygard]

Jay said " it simply means that there shall not be any deviation from the lowest point to the highest point that is greater than 1" in a longitudinal or a lateral direction". In fact it doesn't say lateral. This is the same rule in the DSR rule book and has generally been interpreted to mean a symetrical longitudinal channel can be anywhere in the floor as long as any longitudinal section [FONT=Times New Roman]shall not exceed 2.54cm (1 inch) deviation from the horizontal in any longitudinal section through that surface. [/FONT][FONT=Verdana] This doesn't restrict the lateral distance between any longitudinal section. For instance, section A-A could be six inches above the bottom of the adjacent section B-B as long as neither of them had a greater than 1" deviation along the length of the section. Great way to feed a diffusor don't you think![/FONT]
Marty

[DD16]

I think what a lot of you are saying here shouldn't be included with the rules proposal. If you want diffs, IRS and shocks, etc then FB is the one for you. Same with inlet restrictors. They help maintain parity of powere between mfgs and yrs. . It is the intent of the rules to maintain affordability at the "expense" of cutting edge tech. From reading all the FB posts it started out seemingly to be a low cost very fast formula car. It has blossomed into a class where innovation is applauded. F600 is not meant to be a sibling IMO. Jay and the committe have done a fantastic job with what they believe (and I as well) is the direction that F600 as a starter formula class must take. My opinion, ymmv.

[Jnovak]

Think $COSTS$ guys, if you want all that hot stuff you should do an FB. This is the LOW COST CLASS. All that stuff would add about $10K to the costs. Forget it, not going to happen. These cars will turn great lap times at less than 1/2 the cost of anything else except FV and F5.

I love the enthusiasim though.

Thanks ... Jay Novak

[Jnovak]

Jay said " it simply means that there shall not be any deviation from the lowest point to the highest point that is greater than 1" in a longitudinal or a lateral direction". In fact it doesn't say lateral. This is the same rule in the DSR rule book and has generally been interpreted to mean a symetrical longitudinal channel can be anywhere in the floor as long as any longitudinal section [FONT=Times New Roman]shall not exceed 2.54cm (1 inch) deviation from the horizontal in any longitudinal section through that surface. [/FONT][FONT=Verdana]This doesn't restrict the lateral distance between any longitudinal section. For instance, section A-A could be six inches above the bottom of the adjacent section B-B as long as neither of them had a greater than 1" deviation along the length of the section. Great way to feed a diffusor don't you think![/FONT]
Marty

Your right Marty, we will fix it right away.

Thanks ... Jay Novak

[Bill Bonow]

No dog in this fight, but just curious. Does the committee have an idea what a new purpose built car should cost? I'm familiar with building cars and know that there are a million "depends on" to arrive at a cost. Looking to see if there is a "target range"

As a general comment, I think this could have some serious legs.

As a suggestion, hard tires (think Hoosier R60 compound) are fantastic for low cost starter classes. Make for plenty of fun driving too.

[nulrich]

The latest FC rules have a well written section controlling the flatness of the undertray, and it also describes the measurement method. I can't see any way around it and the intent is captured completely in the written rule. You might consider adopting the exact language. I also think you want the undertray to be flat but not necessarily horizontal, as chassis rake can be a powerful tuning tool.

If you want the entire outer sides of the sidepods to be flat within the 1" tolerance to the outside of the wheels, then you need to say that clearly, as what is currently written is ambiguous (it only says continuous, not vertical or flat). How about the top of the sidepods? Can they have curvature and deviate from a roughly horizontal surface?

These details, like the "sportscar nose," are where I can see lots of potential for aerodynamic development and advantage. You probably want to clearly define the limitations but not necessarily stifle innovation.

I really think you need to list the allowed dampers, and limit it to those that cost less than a certain amount. Let people change the internal valving as much as they like, that's a good place to let owners experiment.

I have mixed feelings about an independent rear suspension. It will make the car more expensive, but it, with a differential, is pretty much necessary for an entry level "formula car." There are ways to make a solid axle work well, but it's still a hybrid of a kart and a formula car, and will reinforce driving habits that will have to unlearned for those moving on to faster formula cars.

I like what you're trying to do, and I understand you have a difficult task making existing designs fit within the new rules. Please excuse my messing up your sandbox! At some point I'd like to design an entry level formula car that costs under $20k ready to go on track, and maybe F600 is the class that allows that. I know it's possible, but I've got a very full plate for the next couple of years at least, so I'm reading these proposed rules with only academic interest. That means I'll share any potential loopholes I see.

Nathan

[Jnovak]

No dog in this fight, but just curious. Does the committee have an idea what a new purpose built car should cost? I'm familiar with building cars and know that there are a million "depends on" to arrive at a cost. Looking to see if there is a "target range"

As a general comment, I think this could have some serious legs.

As a suggestion, hard tires (think Hoosier R60 compound) are fantastic for low cost starter classes. Make for plenty of fun driving too.

Bill, of course this is an unknown right at the moment. Our goal is to be cost competitive with a top F5. A new top F500 (Invader) costs about $21K to $23K ready to race. However there are F5s out there that have a LOT more in them.

I am confident that F600s with the elastomer springs will cost about the same. The MC engines are actually a bit less $$ than a complete 2 stroke drive train including the clutches, pipe etc.

An F600 with coil overs will probably cost about $2K more. We will know pretty soon as we will start building 2 cars very soon, 1 for me will have elatomer springs and 1 for a customer will have springs & shocks.

Thanks ... Jay Novak

[Purple Frog]

Maybe if you spec'ed some import street car's half shafts and C/Vs you could keep the cost down. Just thinking...

Are all those F500 rear axles going to be able to handle the increased loads of 13" wheels?

[Jnovak]

The latest FC rules have a well written section controlling the flatness of the undertray, and it also describes the measurement method. I can't see any way around it and the intent is captured completely in the written rule. You might consider adopting the exact language. I also think you want the undertray to be flat but not necessarily horizontal, as chassis rake can be a powerful tuning tool.

If you want the entire outer sides of the sidepods to be flat within the 1" tolerance to the outside of the wheels, then you need to say that clearly, as what is currently written is ambiguous (it only says continuous, not vertical or flat). How about the top of the sidepods? Can they have curvature and deviate from a roughly horizontal surface?

These details, like the "sportscar nose," are where I can see lots of potential for aerodynamic development and advantage. You probably want to clearly define the limitations but not necessarily stifle innovation.

I really think you need to list the allowed dampers, and limit it to those that cost less than a certain amount. Let people change the internal valving as much as they like, that's a good place to let owners experiment.

I have mixed feelings about an independent rear suspension. It will make the car more expensive, but it, with a differential, is pretty much necessary for an entry level "formula car." There are ways to make a solid axle work well, but it's still a hybrid of a kart and a formula car, and will reinforce driving habits that will have to unlearned for those moving on to faster formula cars.

I like what you're trying to do, and I understand you have a difficult task making existing designs fit within the new rules. Please excuse my messing up your sandbox! At some point I'd like to design an entry level formula car that costs under $20k ready to go on track, and maybe F600 is the class that allows that. I know it's possible, but I've got a very full plate for the next couple of years at least, so I'm reading these proposed rules with only academic interest. That means I'll share any potential loopholes I see.

Nathan

Thanks a lot Nathan, I will forward this to the chairman of the committee and also the CRB.

Jay Novak

[Jnovak]

Maybe if you spec'ed some import street car's half shafts and C/Vs you could keep the cost down. Just thinking...

Are all those F500 rear axles going to be able to handle the increased loads of 13" wheels?

We have done our homework on this issue. To allow the use of IRS & diffs in this class would add a minimum of $5k to the cost of a car.

The axles will not have any problem handling the loads.

Additionally I think most open wheel racers very much underestimate the dynamics that can be achieved with a properly setup live axle. Talk to the 2 National Champions in FF that have raced against our F5 with Brian in the seat at short tracks. On the long tracks the FFs are quicker but not by much.

Give the live axle a chance & you will not be disappointed and you will save yourself about $5K.

Thanks ... Jay Novak

[Brands]

I agree with Nathan on the bodywork rules. They need to be tightened up to avoid some creative interpretation. The old IRL underfloor regs banned turning vanes stipulating a continuous surface. What we did at Élan was to add a turning vane buy simply molding it in one continuous piece with underfloor - a pain to lay up for the laminators but massive aero advantage. We also found that as part of the floor it could have a chamfer detail on it which allowed a knife edge. Again lots more performance. Dallara got their knickers in a twist about it and we're allowed to retrofit there cars illegally to the letter of the rules. Unfortunately it made there car better than ours! Anyway, I think this class has massive potential and if the live axles stays then so be it. Excellent job by all involved.

[Mark_Silverberg]

Personally, I like the idea of a live axle - less complicated, less cost. I do not mind the reference to karts. I am looking at this more as a grown up shifter kart which could accomodate my larger size. I don't need more complexity - I just want to drive. I view this class as more of a driver's class like FV. But the car will sound and look just so much better.