Originally posted by wbp:
Mark, you had an excellently prepared ITC car and now you have the same type car excellently prepared for limited prep Production. For consideration on this subject, could you tell us the difference in preparation costs? Not dollars of course, just precentage.
Bill, don't be silly, my wife reads this forum...I can't do that!
Just kidding, she doesn't care what I spend...
Racing/building a G-prod car vs. an ITC car (Scirocco), the preparation cost difference is in primarily two areas: transmission and engine.
The suspension on my GP car is actually CHEAPER than the one on my ITC if you can believe that. I use non-adjustable race threaded body Bilsteins on the GP car and used special double adjustable Konis inserts w/ coil over sleeves on the ITC car (thanks to the silly IT rules...). The Bilsteins are about 1/2 of what the Koni setup was.
Anyway, the transmission is more expensive on the prod car because of the alternate gears that are permitted. One time expense though, after that the maintenance costs are the same. The gearset costs about $300 more than a stock ITC gearset. (It's made from a combination of ITC and Rabbit GTI transmission components).
Engine: definitely more expensive to BUILD, but maintenance is about the same. I just tore down the engine I have been using for three seasons. In those three seasons I put in one set of rings. Camshafts: $125 vs. $100 for a G-cam for ITC. The biggest difference in build costs in the motor is the cylinder head work (porting, etc.), race valves, lighter valve train components, etc. Probably about $1000 more to build the prod cylinder head vs. the ITC head. However, limited prep would end up only a little more than an ITC head. The rods are stock rods, lightened, polished and balanced. I had my ITC rods balanced (not lightened, that would be against the rules...), so the difference is in the labor to lighten and polish the rods. I use the same ARP rod bolts, ARP head studs and ARP main studs in both engines.
Fuel injection system: no difference. Same setup works for both. I hand polished the throttle body for the prod car myself: cost = $5 for abrasive supplies.
Tires can be slightly more expensive, but only if you want to spend the money. The hardest Hoosier slick compond (R55) will last every bit as long as a Hoosier R3S03 did, if properly heat cycled.
Race gas is required in prod, so that's about $30 more per weekend (10 gals @$5 VS. $2 per gallon).
You could build my car today for less than $15K, and it finished in the top 10 at the Runoffs last year, and I'm hoping to do better than that this year. Try doing that in an ITS or even a Spec Miata at the ARRC (or at the Runoffs next season in the case of the Spec Miata).
A limited prep 1st gen Honda CRXSi (that also runs in GP) could probably be built for the same $15K and finish in the top 10 at the Runoffs in GP as well.
In 2001 I won the ITC SARRC championship (with a little luck). Over the span of a few weeks that winter, I did the following things to the car to convert it to a GProd car:
Took out the 1.6 ITC engine, and put in a former 1.5 ITC engine I bought for $400 (built by Harry Puckett). I decked the block .035" (at a cost of about $50), put an IT legal cylinder head on it with a mild race cam and heavy duty valve springs. Total Cost: $650
Put on a set of Heim ends on the end of stock VW steering arms, and drilled the steering arms for 1/2" bolts. Total cost: about $100. This bumpsteered the car.
Close ratio transmission installed in ITC gearbox w/ limited slip (about $300 in parts and labor to build the 5th gearset). Total (marginal) cost: $500 (transmission needed a rebuild anyway).
Took off the bumpers, headlights, door glass, winding mechanisms, etc. Stripped the dash, interior the rest of the way. Made some flat plates for headlights out of scrap aluminum. Cost: $0
Put Hoosier R55 slicks on my ITC wheels, cost difference: $0 from a new set of R3S03 which I would have bought anyway.
Made some rear window straps from 1" aluminum from Lowe's. Cost: about $5.
Already had the fire system in the ITC car.
The car went on to win 6 out 7 GP SARRC races in 2002, and went 3-5 seconds a lap faster than I ran in ITC at every track I went to that season.
The exact same thing could probably be done with an 1st gen Civic or CRX Si as well.
MC
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Mark Coffin
#14 GP BSI Racing/Action Digital/Airborn Coatings/Krispy Kreme VW Scirocco
http://pages.prodigy.net/Scirocco14gp
[This message has been edited by racer14itc (edited April 19, 2005).]