Thanks Autodoctor, Yes the Boxster is Allowed
This class will have too much Mass to come close to a DSR for speed, the Straight acceleration will be very fun, just too heavy to corner. The DOT Slicks and 3" of ground clearance, remember it is Improved Touring.
Addressing the Downforce, At 100 MPH - The underside of the car will give about 500 to 700 lbs of Downforce for FREE or Almost no Horse Power, But the bigger the tunnels the more drag or Horse Power to push the car. Everything on the top or the side of the car giving downforce will create A LOT of Drag, I think a good number for 1000 lbs of DownForce would be 50 Horse Power at 100 MPH.
The Drive Train Donor cars weigh 3000 lbs or more, the Miata is about 2700 lbs. I expect the Sports Racers to weigh 1500 to 1700 lbs + Driver and 12 gallons of fuel (84 lbs).
A Clean Aero set up will be normal, I hope the top speed will be less than 155 mph
A homebuilder will want to use the donor car to make a Jig to Locate the Engine and Suspension mounting points, then make further small adjustmenst from there. Becarful lowering the engine to suspension mounting points, even 2" may cause problems you'll find later. The Boxster, you'd want to use the whole car to make a Front and Rear locating jig.
I have the 1 1/2" Tube Chassis ready for kit production, I am working on an Aluminum Tub Design with a 1 1/2" Tube Upper Structure, (I worked on a Tiga GTP Light car in 1989 and it will be somewhat like that) It needs to be strong enough to take a hit from a v8 Mustang.
Thanks for Understanding the Idea and not saying it will not work.
Quote:
Originally Posted by
autodoctor911
to connor: Wow, a 2.8L sports racer with ASR aero rules, and modern aero development. That sounds like a formula for some really fast cars. How are those miata or LT suspension components going to hold up to several thousand pounds of downforce in an endurance race, no less? OK, I see that is for the front, still a little weak for a 250-300HP car with high downforce. I would allow the GT version too, as well as allowing any duplicates of the rear suspension used, up front, making spares easier.
I like your concept. I am not sure how many home builders are out there, but it is an interesting formula that could definitely be as fast or faster than DSR, or CSR type cars for less money if done right.
I hope you accept drivetrains from mid engined cars as well(Fiero, MR2, Boxster) It would open up the class to possibly be a PCA class as well. I would love to build a Prototype with a Stock base Boxster drivetrain, and a lightweight tube chassis and ungodly downforce, if it could be done for a reasonable amount of money, and I'm sure there would be a pretty large market for such a car, with all of the Porsche club racers and even those wishing to have a track day special instead of tearing up their expensive late model Porsche.
I think you could gain some traction with this concept if you get some cars built and run them. I think the rules may need some tweaking though, and I wouldn't limit it to IT endurance events.
I think a 2.5/2.7L porsche engined version(200-265HP depending on year) would be the best, most marketable version. If it were to resemble a RS spyder, or better yet, the new LMP car that Porsche will soon release, all the better. Base Boxster engines and transmissions are not too terribly priced, and should be extremely durable. I would be willing to bet that an engine and transmission would last for many seasons in stock form. The Spec Boxster and Cayman interseries(slightly different engine) cars have proven to have very long engine life, with very few, if any failures.
P.S. I would suggest allowing base Boxster engines up to 02 for the current 2.8L class, unless there are other engines available with more than 217HP, then there is the 03-04 2.7 with variable lift cam(245HP). If the 217HP is too much, the 2.5 used from 97-99 is under 200hp, but more limited in supply, and less reliable. If you are just limiting to 2.8 L engines, the the 265HP direct injection 2.7 from the new(2013up) Boxster would be killer. The engines are fairly heavy though, as are the 6 speed transmisssions. It may be prudent to allow the more powerful engines at a higher minimum weight with driver if the cars are not using much ballast with the lighter engine options and a larger driver.