Hey Marshall,only thing itr will cost of e36 325bmw's is some new vinyl and a bunch of hours spent finding things to take off the car to make it lighter. since we can't do bigger brakes, bigger wheels just mean more unsprung weight.
unless we all dump our 325's to get z3 2.8...somehow they got classed with the bigger engine at the same weight as the 325....hmmmm. hopefully that was one of the mistakes in the fastrack version of the class list.
marshall
marrs itr #64
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Jeff right, the Z3 may be an e-36, but it's got the rear suspension of an e-30. Secondly, the inital hp is very close to the same as the m-50 2.5 single vanos. The Z3 also looses on aero and as the wheel base is shorter, it's not as stable. A friend of mine (Tom Bell) that runs a 2.8 in BMW club JP is going with a 328 sedan as all the tracks out here favor a car with more stability.
Jeff,We are working on fixing the engine classifications on the BMW cars, but note that the Z3s have a far less sophisticated rear suspension than the E36. So, some weight compensation is appropriate.
How much more power will the 2.8 make over the 2.5? We've wondered on that one quite a bit.
What amazes me the most about this whoel situation is that, all arguing, spitting and cutting aside, the plain hard numbers show that the E36 at 2850 has a better power to weight ratio than anyother ITS car. Period. That's why rookie drivers and/or non-full prepped cars run up front. A lot of this talk from the BMW camp seems to stem from the fact that it will now take full prep/well driven efforts to run up front, whereas before the misclassification of the car created a situation where the E36 was clearly the car to have.
It's funny, as I've gotten better at this sport, and improved my car, I've raced with RX7s and 240zs and 240sxs in the back of the pack that were learning with me. Never did see a slow E36......
Will the 325 be as competitive in ITR as it is in ITS? I hope not, because that was the plan. Make it run in a place where it takes a full prep effort to run up front. And that, gentlemen, is fair -- although I agree the mess with the SIR, the timing, etc. was not. But remember, the whole reason the car ended up in that mess is because it was classed wrong from the start.
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While I don't have a dyno sheet, I've been in contact with the builder of my motor. The current set up includes the cam-shafts from a s-52, and a TEC-II stand-alone computer. The rest of the build is stock rods, crank, pistons, in other words verry IT like. With this the rear wheels dyno'ed to ~210hp, assuming 18% driveline loss that's ~240hp. The question I don't have an answer for is how much will I loose with the stock cams? One other thing that I learned was that the M-3 cams were tried in the 2.5 and resulted in a very peaky power band, whereas they were a better match for the 2.8. This build matches the specs for World Challenge circa 99-02 when e-46 328's were running. In '02 I believe that the rules were changed to enhance the power of the M54b25 2.5, with aftermarket rods, cams, solid lifters, and pistons these motors see red-lines above 8500 rpm, where as my motor will have a hard limit set at 7200 rpm with it's hydraulic cams. I suspose my car would make a great Lime Rock Special, too bad I'm on the other coast.
James
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