Diff Ratio?

[dgerny]

I have a 93 325is with a 3.15 lsd. At the moment I drift on a go kart track (Pats Acres), I am usually in 1st or 2nd and even then I am usually in 1st. I was wondering if anyone who has switch from a 3.15 to a 3.93 would say about the change. I know the acceleration is increased would be good because the straight away is about a 50 feet till the first corner so anything to help with acceleration is nice. please add you 15 cents about the swap.:help

[protomor]

I liked the 3.73 with a factory M20. 4.10 was too short.

[Piner]

3.91 would probably be pretty good. I would think.

[dgerny]

That's what I am thinking now do I convert the lsd I have to 3.91 or buy a 3.91 diff then weld it so I can have 100% lock?

[jeepster]

Here is my experience. My car 94 325is full bolt on M50.

3.15 LSD was awesome in 2nd for some of the medium bigger tracks. third gear was not an option....I could momentum drift it but not power drift it. 3.15 in 1st and second was good for the go kart track here, but on the tighter stuff when I bogged 2nd I had to downshift (clutch kick was only somewhat helpful). 2nd was awesome for the local parking lot events!

3.91 welded was great in 2nd for the go kart track. Much better acceleration and much more smoke with no shifting. Third was now and option for the larger tracks as I could hold the drift if I entered fast enough. The parking lot course (medium sized) I found myself between 2-3 at several spots, 3.15 was better here.

Have both on hand and get really good at changing them (I can do it alone in about 45 min now..25 min with an extra hand)! For what you are doing the 3.91 sounds like a good option.

Or keep the 3.91 and do an LS1 swap! LOL

[dgerny]

All I can think about is ls swap. all you fuckers with your v8s make me want to do it so bad. especially you with the v8 swap 50 cars.................

[protomor]

Ah yea OP is an E36. I was going for E30 where the factory ratio is 3.73. The E36 factory ratio is 3.25...ish? So a 3.91 would be short and zippy. I got a 4.10 in my LS now. Was running a 2.93 in this video
https://www.youtube.com/watch?v=_-aBvBIRLrU

[Gmfwd]

I ran a 3.15 for a few years. Just put a 3.91 in but havent tested it yet.

Every track is different. I have mine setup for the 2 tracks I most often drift, somewhere else the setup might not work well.

[dgerny]

Well. The transmission is grinding when I shift into 2nd. :alright
Guess the clutch kits and trying to quick shift:buttrock didn't help the
trans.

Got any suggestions? Rebuild it just buy one off craigslist?

[jeepster]

Drift it till it blows! Seriously, just slow your shift down a half second. We are not drag racing here. the clutch kick will not affect how it shifts.

[dgerny]

It grinds into second no matter what I do.. :'(

[Piner]

just get another one, way cheaper than a rebuild

[Jdmark7]

Try out a welded 3.91, I just did pats acres for the first time last weekend and my 3.08 (e46) was awkward, 2nd wasn't enough power and 1st would hit limiter often

[dgerny]

Try out a welded 3.91, I just did pats acres for the first time last weekend and my 3.08 (e46) was awkward, 2nd wasn't enough power and 1st would hit limiter often
I had the same problem and I saw you there! your car is wayyyyyy to low for pats! go off and say bye bye to entire under of the car