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Ron Stygar Carl Buckland Dale Beuning Forums Help
From digest.v6.n276 Tue Feb 25 12:37:09 1997 In a message dated 97-02-25 02:09:56 EST, you write: << Subject: <E36 M3> 95 vs. 97 Suspension calibration Here is the question to E36 M3 guru's. What are the differences in suspension calibration between 95 and 97? I'm thinking about moving up to M3, but I've heard that 96 and 97 cars have a lot more understeer dialed into them. If this is true, I would have to shop for 95, or wait for Z5 to come out. >> Actually, the post-95 cars have more potential for oversteer. Little known fact (whispering), 95 rear swaybar is 19 mm, post-95 is 20 mm, results in an actual rear roll-rate increase of 25%, everything else being equal. The difference is in the rear wheel width, 95 was 7.5" EXCEPT(!) for Forged Wheel Option which was 8.5" same as post-95. This will increase understeer vs. 7.5" (all else being equal), but is easily overcome by using less rear toe-in, and possibly toe-out, than spec'd. Also, spring and shock rates were increased slightly on post-95's, however we haven't done a comparison of the differences and don't have the actual rate changes. They're probably very small and aren't worth considering. Front camber was decreased slightly and front caster increased slightly on post-95's, changes are so small that any effects are negligible in performance handling. Biggest reason for understeer on E36 M3's is shocks. Call TC Kline Racing (or Dinan, too) at 614-771-7744 for rebound-adjustable Koni's (highly recommended over anything else. Only our experience-based opinion, please, no flames or argumentive e-mail). Increasing rear rebound will help rotate the car during turn-in. Biggest difference is the engine. Despite BMW's claims and numbers, our testing shows post-95 3.2L engine as having considerably less performance above 4500 rpm, mainly due to the decreased intake runner area of the 328 intake manifold vs the 95's 325 manifold. Biggest potential is for 3.2L internals in a 95 3.0L motor (we're not sure if this is possible, anyone care to comment?) since the manifolds won't swap due to mounting differences with the heads (we've heard, please correct us if we're wrong). Welcome to the wonderful world of OBD2, this is why BMW increased engine to 3.2L (actually only 3.15L for US versions). Displacement had to be increased to make up for performance lost in designing compliance with OBD2. We tested the 20mm bar on our stock 95 M3 to see what effects it has on handling. It will definitely dial out understeer. However, it's not legal for SCCA stock class autox'ing. It's for sale cheap if anyone with a 95 M3 or other E36 BMW wants it. Just private e-mail us and it's yours. Mark Sipe |
