what diff ratio should I use?

[olscooler]

Car 91 325i with M30 with 10:1 compression 1mm overbore CP forged pistons, Schrick cam 284/280. Currently running a 2.93 gear ratio and it takes forever to for it to get to red line, not impressed the way it goes. The po said a taller diff would make a big difference, can anybody chime in with what would work better, I don't track the car but I do get out of hand once and while out on the back roads. Thanks

[golde30]

3.25 from an e28, 3.46 also from an e28 i think, 3.73LSD out of any e30 325is? theres alotta options, depends on what yer looking to get out of it.

[MR 325]

3.73 is too short of gearing for the M30. I'd go with a 3.25 personally.