"Awesome, thanks!
So from what I gather with the Wavetrac you had to send them your stock diff for modification since it is a welded ring gear or do they send you a unit and you send back a core? Also, I don't see an M240i application with the 2.81 ratio. EDIT: Nor the Wavetrac option at Turner."
Yes, Diffsonline did put a diff together according to my specs. You send the original back after the install or there is an additional charge. Turner doesn't do the diff itself but works with diffsonline and wavetrac. They may even run some of the wavetracs in their race cars, not sure.
I went with a 3.46 ratio. I was worried it may be too extreme but now that I have experience would even consider going more aggressive. I had a sligthly larger diameter winter tire for a while and didn't like the change in final drive ratio. I should mention that I saw the need for a higher final drive ratio in my other BMW too. Which spins to 14200rpm. I like revs, what can I do
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