More thoughts on the rules
I would suggest that the chassis rules be unchanged from the current FF/FC. The advantage of aluminum monocoque for ultimate strenght will favor that construction over tube frame. The aluminum tub is more costly to build and less durable. When aluminum tubs were the fassion, the top teams had two tubs per car and would change out and rebuild each tub once to twice a season. The temptation to push the envelope as Swift did with the DB4 would be way too much for constructors.
Again the emphasis should be on appropriate technology for the end users -- the SCCA club racer. With careful thought you can write rules for a formula car class with awsome performance and at a very reasonable price. I would estimate construction cost for new cars at $30,000 new and entry level cars at $10,000. With volume and shareing components among manufacturers you could drive the costs lower.
I would think seriously about lifting the restriction on airfoil construction. It may be that carbon is the cheepest way to build. It needs to be studdied. I don't know.
In an earlier post Stan addressed the safety of the chassis construction. Currently the GCR requires heavy wall tubing as diagonal braces in the cockpit bay. I know that the Citations that I have produced since '94 meet the rules but I don't think any one else does. If we were to enforce that rule and increase the thickness of the side body panels from the foot box to the roll bar to say .060in (that would be 8 layers of Kevlar vacumed bagged) the crash protection of a tube frame would equal a monocogue.
I would think about restriction brakes to 2 piston calipers. 2 piston calipers will run from $100 to $300 which is the price range for current calipers. 4 pistons are double that. Wilwood calipers are cheep but Brembo, Alcon, AP and PF are not($600 to $1500 each).
I would put a lot more study into the engine restrictions. The AMA races these engines. We should see what their experience is. Talk to the manufacturers. Air restrictors could lead to very costly engine development programs as the ECU were never programed for manifold vacume readings that would result from air restrictors. An alternative would be to dyno all the allowable engines and rev limit them to 155 hp., say 11000 or 12000 rpm. Each make of motor runs a required ECU. You control the ECUs by collecting the ECU prior to the race and drawing for the one you use in the race. Maybe a single ECU will work for all engines. I don't know but it will be one of the tougher issues to get right.
Steve Lathrop
What are the rules intended to do?
I am confused about what is intended by this set of rules.
Are we writing rules to encourage the manufacturing of new cars or are we trying to write rules to allow a large number of existing cars to be converted to motorcycle power and compete?
Are we trying to build cars at in the around $30,000? Or do we want $50,000 plus race cars?
If costis the purpose of this exercise then the FF/FC rules should be the base from which we start. Change just a few of the restrictions of the FF/FC class and you will escalate the cost of new cars.
You are right about aluminum monocoque tubs being old technology. But at the end of that erea tubs were bonded aluminum skin and honey comb structures, very strong, very light, and very expensive. Once the structure started to delaminate the whole thing was junk. If such technology is allowed I would have to design to it because of the competitive advantage. Look at the Swift DB4 experience. This technology will add a minimum $10,000 to $20,000 to the cost of the basic car.
I know that Wilwood brakes are cheep. But the Formula SCCA car did not use Wilwood brakes. They used AP units at $500 each. We just added $1200 to the cost of building a car. If there is a performance advantage then it will be the standard.
Engines are not my business. I agree that they need to be reduced in power to 150/160 bhp. What ever we do should keep the engines as close to stock as possible. Ideally the engines should be fully competitive as delivered in a new stock condition. Again start allowing any preparation above stock and up go the costs.
We have decades of experience with the FF/FC set of rules. These cars still require very good engineering to build competitive cars. The advantage is that the tooling is very inexpensive. In low volume production we can cut the cost of tube fabrication by having all the tubes CNC bent and coped. The assembly time is cut by two thirds. To do a composite tub you will spend $250,000 in tooling, compared to a few thousand dollars for a chassis fixture.
Obsolete technology implies no improvement after some point. In 1978 when I built the Zink Z16, we tested that car at 1000 ft lbs. per degree torsional regidity. An aluminum monocoque Zink Z14 FSV was 4000 ft lbs. per degree (that car weighed 872 lbs with balast). The last Citation FF we tested was 5000 ft lbs per degree. Based on our FEA modeling, we expect the new Zetec FC to come in at better than 6000 ft lbs per degree. The frame weights have declined from about 110 lbs to less than 80 lbs for the latest car.
Right now you have two people in this country with proven models ready to produce cars to the current FF/FC rules not to mention the imports. D sports is heading for a trouble because there is almost no limit to the cost of one of those cars. I can see the F1000 costing half the price of a new DSR and delivering equal or better performance.
As an aside, Richard has just completed the new Variloc chain drive differential. This is step one in building an F1000.
What is the demographics of our target customer
A lot of the argument about rules is more about the market demographics of the potential driver/owners.
Stan and Lee are arguing for a car that is competitive and priced around the Formula Mazada (new pro car), formula BMW and pro Zetec F2000. Is SCCA club racing attractive enough to draw those customers in sufficient quanities? All of those cars cost more that 100% of medium income. How many SCCA club racers can afford to spend $100,000 per year racing? How many can afford $50,000? My advice to customers is to figure how much money you can spend on racing and buy a car that is equal to half that amount. That implies customer incomes in the low to moderate six figures. I figure that a young, unmarried, die hard racer can afford to spend 50% of his income racing. I don't have an answer to this question but we better figure it out before we proceed any further.
The car that Stan and Lee are advocating has a lot of competition for customers. Why not pick one of those classes and say here is an SCCA class and come race with us. That would be more cost effective than trying to compete with the similar package.
There are a lot of reasons that Enterprises has not been able to introduce a follow on to the spec. racer. Not the least of which is that "spec" classes do spec the cost of entry and there are not enough customers with the income and desire to make the classes viable.
I look at my customer base over the last 30 years and I do not see how the vast majority could start today in what we have to offer in racing classes. F500 and FV are very specialized and have limited appeal. FF and FC at the turn key level are way too expensive. I see the F1000 as a way of reducing the cost of FF or FC by 20% to 30% both to purchace and to maintain.
I hear more voices on this forum arguing for the low end class. The real genius will be in devising a set of rules that balance cost and performance, and bring in a car that will attract reasonable numbers.
Steve Lsthrop
Demographics and appropriate technology.
The fact that we haven't build a new car in 11 years may explain more about the car market than our failure as a car building company. If you look at the run offs, our cars have been competitive in both FF and FC each of the last 11 years. Our customer base has not expanded over the years. That is also ture for the classes we serve.
Look at all the versions of Van Diemen that have taken a run at us. The truth is that if you brought a 94 Citation to me it would cost $10,000 to bring the design current. We have been fortunate that we have not had to build cars to keep the parts business.
Personally I think Marshall's suggestion for 600cc class aimed more at FF performance is really what is needed. That would be a ture entry level class. My support for the F1000 is because I see it as a first step. Having two classes based on the same car really is attractive to builders.
I ask Stan and Lee if we go with your rules how do we compete with the other formulas in that price range? Look at where the numbers are in club racing FV, F500, FF, and FC, plus off shoots of those classes. That is your demographics. The trick is to design a class that 10% to 20% of racers and potential racers in those classes will look to buy new cars. FA has never been a big class in club racing and that is the type of car you are advocating.
Stan, you are wrong about tube frame technology being 40 years old. It has its roots in aviation dating back to the 1920's. Practically every aerobatic plane built today uses a steel tube fuselage because it has a better weight to strength ratio. The Lola T97 Indy Lights car used wood in that chassis. The quality of a car is more the engineering effort that goes into the design and construction than what you choose to build it out of. I had this same argument with Paul White in the 80's about aluminum monocoques. They were stronger than tube structures but they were not even close to being as durable. As such we were wise not to change to aluminum monocoque construction for FF, no FC then.
I also do a lot with crew shells. Those are carbon composites. They stay together for years. But they de-laminate after a few years. Once they start to delaminate the performance of the boat deteroriates significantly. It looks good and still floats but it doesn't go fast any more.
When we build race cars for club racing we need to think of what the car will be like in 20 years. With the continuous advance in tires the old cars are being stressed well beyond the original design. In the '70's you never expected a FF to do more than 1g in a corner. Today they can do 1.8g and sustain it. (peak g's for turn 1 at MO). The tube structures are much easier to repair and modify to deal with increasing loads. We need to stay with that technology!
Steve Lathrop
Maybe this is three classes
I think there may be room for all three designs being proposed here...
Marshall's idea of a 600cc car in the tradition on FF is a good one. Some guys in Canada have been at this for years, calling it F4. With the untenable motor situation in FF maybe a F600 class would garner some real interest. Keep the rules like FF (tube frame, no wings, small tires) and you would potentially have a cheap class that would have all of the FSAE guys drooling. Target prices at current F500 level or very slightly higher - $20,000.
I personally am interested in a F1000 class that tries to limit investment. Basically FC like chassis rules, with limited track and wheelbase to keep chassis from going obsolete all the time. Allow wider sidepods to allow Speads/Jedi/Gloria/OMS cars to compete too. Maybe allow 8/10" wheels to reduce tire wear, but keep the bottoms flat. Consider a "gentlemen's agreement" to run stock production motors only (with mods for dry sump/exhaust type stuff. Target price at 'volume' SCCA racer market - under $30,000.
Finally to placate the 'no rules' crowd. Allow a FA like chassis wiith bike motors prepared to the current CSR rules (up to 1500cc). This could be a carbon tub/tunnels car that truely kicks the @ss of cars like FBMW. For the "uber racer" that has money to burn on his/her club racing. Target price - Well if you have to ask...
Sean
