Diff.

[///Sniper535]

How will my top end be effected if i swap out for a 4.27 LSD on my '89 535?

[winfred]

3.91 to 4.27? it's been suggested that you may gain a couple mph with the better mechanical advantage, i never topped out my 535ia but on the happy side of 135 it still had noticeable acceleration

[///Sniper535]

3.91 to 4.27? it's been suggested that you may gain a couple mph with the better mechanical advantage, i never topped out my 535ia but on the happy side of 135 it still had noticeable acceleration

Are there any negative sideffects from going to a 4.27?

[winfred]

it goes faster and if you drop the old one on your foot it could hurt

[gale]

Assuming your 89 presently has a 3.91, the rpm's at 80 mph will increase from 3000 to 3300 with a 4.27. Adverse effects from running a 4.27 should be minimum. The factory made them std. on 91-93 535ia's. Back when mine was still an automatic, I would have put a 4.45 in it if they weren't so expensive.

[///Sniper535]

Will my top speed be decreased?

[Johntee540]

Yes. There is a great set of resources on the Koala MotorSports Website for calculating the differences between where you are now and where you want to go. I just bought the 40% LSD / 3.15 Diff from them to put on the 540/6 I have. It is a wonderful difference - especially since I am running 18" wheels. - JT