ive contemplated it. i have a complete t2 driveline to spare and my car is a 1990 gtu. i was wondering. how darn strong is the na rear end? i mean really? mazda trix sells driveshafts that fit just fine. why would they sell them if the rear end wasnt strong to begin with?

would 300 whp be pushing it?

 

What are you planning to do with it?

For street use and light track use (autocross/HPDE/etc), I don't think you'll break the NA rear end. For drag use, you'll probably break things.

-=Russ=-

 

ah. i wont go to the track much. plus, on the streets, if i do bash on it kinda hard, the 205 wide tires will break traction before anything else breaks i bet. i just need to change the fluid and whatnot.

 

its an old diff, the axles go b4 the diff

 

I've heard of/seen a few guys running 11's and 12's on S4 NA LSD's with a turbo swap and they seem to be holding up fine.

 

v8 swap guys also often keep the n/a rear end too.

 

We've have broken two stub axles on NA diffs, and the diffs are still fine. The stub axles a perfectly designed to break with oil grooves cut in them that cross. Its like they put a dashed line like on toilet paper for it to "tear here"

I don't think you could make it worse design if you tried.

We are running about 235-250 flywheel HP through them on 9.5in wide slicks.

 

That why right there! slicks and what, luanching at 6k rpm's? Alot of v8 guys swap the 3.909 rear pumpkin becuase its sooted better for a v8 swap and they dont have too much trouble with it.


But a t2 diff will alway's be stronger and more practicle for drag.

 

Slicks and roadracing, no drag starts.

 

I wouldn't run a NA rear end with my V8 conversion. Wouldn't even dream about it. But I mean I love drag racing, and street racing and with drag radials that are 235/60/15 and about ATLEAST 450+ wrhp I would be snapping them. But I mean I would put it in and try to sell off the old stuff while you can get something for it before you break it or something you know what I mean