I know you guys tend to break EVERYTHING in the rear end. diff case, lsd and the ring&pinion

but I was thinking of swapping out to a FD torsen in the future and was wondering at what power levels they start breaking.

I searched a little and didnt find a whole lot of good info on any specific rwhp levels of teh guys who were breaking them.

I don't plan on running ET slicks or anything but will run really sticky street tires and I do tend to abuse the **** out of my clutch. No drifting though, just clutch diffs and burnouts for the hell of it.
-Ben Martin

 

thinking off the top of my head...around 600+HP...But there isn't much talk about the Torson unit failing...For your TII it should be fine...there a good bit of info on this in "your" section.

 

You can blow the diff with less than 300 rwhp if you are drag racing.....stick with the TII diff.

 

ok so my head is off by a few HP?? LOL

 

my car isnt for drag racing, but road race/auto-x and mtn roads.
planning on about 300-350rwhp.

ill do some drag racing but not much of it, and only w/ my daily street tires
im going to have all mazda competition mounts but those are still rubber.

 

The torsen diff is the best diff for auto crossing, and road racing in my opinion..

Clutch type diff best for drag racing and dirfting.
viscous Lsd... is pretty shitty as the lock up rate is pretty bad.. only good for snow and rain to help traction.. not really a performance.

not sure on the breaking point.. I know a few people who road race the FD's with well over 400lb/tq and they have had no problems.. also know a few LS1 guys with no problem with the stock diff handling the torque on a road course... Although I'm sure it wouldn't take much to break them with slicks and dumping the clutch from 6krpms.

Hope that helps.

 

thanks for the reply trainwreck
godzirra!!!!!!

 

Yeah, the diff can take a lot of hp...500+ rwhp if you are road racing or auto-xing. It's the hard launches that do it in, and it really doesn't take that much power to do so.

 

Just don't drive highway 1 like a crazy clutch kicking everywhere and the stock TII rear end will be fine. Mine's been just fine. Though mine is pretty stock-ish. Ive always read the S4 TII diff was stronger then most in terms of 'breaking things'/abuse being taken.

 

It's shock that breaks the FD drivetrain, not torque. If you shock your drivetrain in autox or road racing, it's because you're a shitty driver.

Drag racing of course applies heavy shock loads by nature.

How much torque you have on hand certainly affects whether you can break it, but how you drive and how sticky your rear tires are determines whether it will break.

Dave

 

I completely agree and will add that wheel hop is usally the culprit as it creates hugh shock loads.

 

^ Good point darksideperformance, forgot about that.. if you get wheel hop, you will definitely break things.

 

I guess you've not tried a SCCA ProSolo. Drag start followed by a full course.

 

If you understood my post I think it should be clear what adding a drag start to any driving activity does to the drivetrain.

Not to mention that the kind of driving Ben has mentioned have very little in common with ProSolo. You don't just accidentally get entered into that kind of race.

Dave

 

The Torsen is better for auto-x and road racing.

If you are dropping the clutch at the drags, then it is not the best...

 

My post was tongue-in-cheek, but I didn't take the time to find the right smiley.

 

No worries. I'm a little dense sometimes.

Dave

 

Well I know this is a late response but in case anybody is searching in the future...

I knocked a few teeth off my Torsen during my first drag race with around 350 Dynojet rwhp (dyno-ed at 310rwhp on a Mustang dyno). Culprit was most assuredly wheel hop. Was running Yokohama A032s at the time.

Boy those things sure make one hell of a nasty slamming noise in parking lots once you lose some teeth...

Replaced it with a KAAZ. Sure makes drifting fun, and drag races shouldn't be a problem anymore, but the car pushes pretty badly now when on the power, in comparison with the old Torsen. Don't think I reversed enough plates in it so it locks up a little too much. Also causes the car swerve to the inside of a curve if you're accelerating and then let up enough for it to unlock again. Guess you can't have everything.