What diff gearing should i use?

[alpinee30m50]

I have a 2.93 open diff in my e30 m50 5 speed swap. Needless to say, this needs to change. I want good acceleration and i dont really care much about top end as long as its up above 130 or 140. So what gearing should i use?? Im definitely going lsd but im not sure if i should use a 3.73 or a 4.10. I dont wanna be shifting every 3 seconds but 4.10 might be fun for acceleration.

any thoughts guys??

[asubimmer]

well for starters you should post what tranny you are using. You prob want a 3.73 though.

[Liam]

3.73 is probably your best choice no matter what trans you're running, the 4.10 is pretty much "just plain short".

[CrazyGhost]

I went from 3.15 to 3.91 in my m50 project. Probs a tad to high so i would definantly go for the 3.73. With the jump in diff ratio i went with i also found i lost about 80-100kms total driving distance to a tank coz of the higher fuel consumption. Cheers, Ryan

[alpinee30m50]

im using the stock getrag 260 from the 84 eta. I was thinkin 3.73 also, i thought 4.10 would be pretty high. Yeah fuel isnt a huge issue for me so all well. But yeah thanks guys, i think this is the only forum i have been on thus far were i can get good answers for anything!! lol

[Knockenwelle]

By the math, at 7k in 5th gear, with 15" wheels and a 4.10 rear end, my theoretical top speed is 142 mph. Sure, there's plenty of stuff that'll blow by on the BIG tracks, but for just plain screwin around and having fun on smaller tracks, I like the tall gear. I'm also using a Getrag 240, which has closer ratios, but the 5th gear ratio is only .05 different than the 260. I love rowing gears, but depending on the craziness level of your build, I dunno if you're gonna need to be rowing all the time...

I've also found 3.73 to be about a perfect gear for almost anything. 6 vehicles (Chevrolets from 1966-2003) in my family, none of them stock and all of them fairly quick, all have 3.73 diffs. These include musclecars, late-model Power Tour types, and trucks.

[MR 325]

3.73 definitely.