Rauq

iTrader: (1)

Hi guys,

New around here but reading everything I can. I've been in the GTO scene for a while but am fairly new to live axles. I'm planning a turbo M6 fbody build and I'm focusing on the rear end right now. I keep reading over and over that the 10 bolts are weak, they'll break with power and especially an M6 in front of them, they're weak, they're weak... my question is what's the weak part? Is it the 7.5" ring and pinion?

Corollary to that is the next question- is there any strength advantage to going to taller gears? I've only followed people putting in 3.73s and 4.10s for NA cars but I would consider going to an A4 rear to build boost. Is there a possibility that, if the gears really are the weak point, that going to something taller will be stronger, following the line of logic that fewer teeth = stronger teeth? I know an A4 is easier on the rear but perhaps part of the reason why they're slightly less prone to dying is the taller gears?

01ssreda4

iTrader: (96)

Basically the whole thing is undersized. Axles and posis are the #1 things I have seen break. Also, on the Torsen rears (99-02) they tend to have their case bolts back out, and then proceed to get chewed up by the gears. Gears aren't safe from breaking either, especially behind a hard hitting clutch. A soft stock clutch will give the rear a chance, but even then it can be short lived.

Rauq

iTrader: (1)

Do you have any ideas as to what might already have a strong rear end in it? Something known for its diff? This is throwing a wrench into my plans for a budget turbo build... Friendly competition with a friend's 89 535i, he's got a Cummins turbo on the way...

Capricio

Throw a girdle on for a little insurance:

http://www.ws6project.com/user_stor/...oducts_id=4539

That's about all there is in the "cheap and easy" category.

bwkmaro

i have a v6... and mine blew still, its not the parts that are really the weak point its the casing it self, when under a heavy load the casing actually streches and allows the gears to move apart

heres mine after a 2nd gear pull right on the edge of breaking 295s loose

^also had a girdle

01ssreda4

iTrader: (96)

Nothing that bolts right in if that's what you are getting at. 12 bolts, 9 inch, and s60s are the way to go. Lots of vendors take these centers and modify them to be direct bolt ins. That is the only way to go IMO.

Rauq

iTrader: (1)

I could go as far back as a Vega or Chevette, it's looking now like the rear end is the most important part to start out with already in the car and not needing modifications. I'm settling in on an LQ4, Viper T56, and two .76 S200 turbos.