What LSD ratio are you using

[Jean]

Hi,

I am pulling my m30b35 out to get it ready for m62b44 swap with e34 530i 5speed transmission.

I am currently using s3.46 that has worked great so far (its a rebuilt lsd with 4 discs), but I am afraid this ratio won't work great with m62 swap.

I need my 2nd gear to top out around 65-70mph to make the best use of the car in autocross, so that a shift up/down 3rd isn't necessary.

What do you guys use, and what are your top speeds in 1/2/3rd?

Current tire size is 225/45/15 on 15x8 wheel but next size is 265/35/15 on 15x10.

Looking forward to hearing what's working, and how you like it?

thanks

[SuperchargedV8Touring]

Hi Jean,

I have chosen to use the standard 6 speed out of the E39 donor car, linked up to a 3.07 lsd from an E28 M535i.
It's a big case diff and needed some tweaking to fit in the right area, but it has now got twin mounts for strength and I've had some custom driveshafts made.

Just as a point of interest, the E28 diff will connect straight on to E39 driveshafts and the E39 shafts will overlap the E30 shafts, so you could 'cut and shut' them, although I understand they would not be tempered and may snap under the torque loading.

I used this to help work out my theoretical top speeds etc:

http://xse.com/leres/bin/gearratio?titl ... 0&wheel=15

If this link works, it should come up with my 225/50/15 tyres on a 3.07 diff ratio and the standard 6 speed box ratios. You can change all the bits you need to help work out ideal diff ratios and tyre sizes.

As you'll see, my car's set up is not ideal for you, but I chose the 3.07 for strength and relative low cost. I'd love to have a 2.?? lsd so that I could have an easy 70mph 2nd gear!

Best of luck with it all.
Cheers, Michael.

[FormerMember]

I've 3.41 LSD with 245/35-17 rubber and revs limited to 7000.

Maybe a tad too high ratio for highway (around 3000rpm @ 75mph), but due to higher rpm-limit it tops at 175mph / 280kmh (tested on dyno while optimizing ECU) so there's plenty of potential

[Phill172]

Mine is either a 3.91 or 4.1 cant really remember, top of 5th gear in mine with a E34 530 5 speed box is around 120-130mph.

If you have just had a rebuild on the lsd give it a try and see how you get on?

Second gear is about 55mph, 3rd gear is around 80ish....really doesnt use the V8 power well but its perfect when im drifting

[Jean]

Yeah, I must have a 2nd gear that goes over 60-65mph so something like 50-55 won't work at all for me.

thanks for the responses!