BMW Transmissions on SR20's

[gills]

Great update. Quick update on my CD00A firstly, I've run 4 AER endurance races on this transmission (88 hours racing) and the synchros seem to be ok. At the last race though, the last stint driver reported something with 2nd gear grind leaving the pit, but that could just be heat of the moment type thing. There also seems to be a significant whine that's developed that's proportional to road speed. That's usually diff related, but it's possible it could be something on the output side of the transmission based on a quick ear test when we got home from the race. Car is going under the knife soon....


Back to your post... So why not the 5 speed ZF's from all of E36 (including M3) again? The 5 speed ZF's are basically identical across all E36, including M3, with only minor internal changes AFAIK. There's a ton of them and they all bolt up the same to the M5x/S5x family. The ZF 5 speed also has the same gear ratios as the E46 M3 through 5th gear with the 6th gear just being an over drive. People who road race E36/46 actually prefer the ZF 5 speed because they are more robust.

And, I think I've already mentioned this, but the final drive gear ratios in this family of BMW's are typically lower (taller) relative to anything from Nissan with the exception of the E46 M3, which I think was a 3.46(?) as it was able to get away with that since they reved to ~8200rpm. I guess an SR can achieve that easily. I'm sure you've probably mathed out what would be ideal for you.

Regardless, hugely interested in this to mate up to my VQ. If my CD00A is indeed unhealthy, this may have to happen on my car also. Helps that I have a ZF sitting in my garage staring at me every time I go in there.