E30 rearend strength.

[dazz822]

How much can the rearend of a 325is hold powerwise? Looking to do a swap and see that some cars like the 500hp rb26 e30 just has an m3 diff. Can the rearend really hold that without snapping axles?

[Danny]

yes.

[dazz822]

yes.

Wow thats pretty amazing, i've been worrying about that for awhile. Any more info on cars that have the kind of hp (300+) and how their rears held up would be nice im searching the site now.

[blueapplesoda]

axles are fine...just make sure you get the larger diffs...i believe we have small case and med case. stick with the medium case ones. I have been running a medium case 3.73 and was drifting/launching, circuit racing, all sorts or stupid abuse and it was perfectly fine.

I found a 3.23 small case and put it in, and blew it up last night. Don't try to drift on r-comps with a small case. I never would have thought I'd hear that terrible broken-axle sound that hondas and such have so often, but it finally happened in all the years of abuse.

[Supadave]

axles are fine...just make sure you get the larger diffs...i believe we have small case and med case. stick with the medium case ones. I have been running a medium case 3.73 and was drifting/launching, circuit racing, all sorts or stupid abuse and it was perfectly fine.

I found a 3.23 small case and put it in, and blew it up last night. Don't try to drift on r-comps with a small case. I never would have thought I'd hear that terrible broken-axle sound that hondas and such have so often, but it finally happened in all the years of abuse.

When u swapped the from a small to med or med small do you need to change your drive shaft? Or does it just bolt right up??

[Supadave]

http://www.metricmechanic.com/pdfs/metric-mechanic-differential-booklet.pdf

[MTechnikII]

The E30 rear end is not that strong, most Z3 M roadsters, have broken rear end sheetmetal parts, nad bent diff suports, and they are only 240hp, if you see inside a trunk of an Mroadster under the carpet you will find spotwelds breacking and sheet metals bending
Henry

[AndrewBird]

I think he is talking about the differential, not the rear end of the unibody.

I think what saves them from being destroyed is the lack of grip. Pretty much everybody that has 300+ HP has traction issues into 3rd. If you can't get grip, then you can't really break stuff. I have heard of people twisting CV axles with turbo cars though, but I think it's rare.