to sum it up im thinking my rear end is moving around to much. under hard acceleration the diff. moves around more than i like. im sure i could find some polyurathane bushings but does anyone know of a type of brace or traction bars that would fix this? even something close or ideas would help because i might be able to weld something up. thanks all

 

Just get new mounts.. My car launches hard as hell, and i don't have anything like a traction bar..

 

really thats it?

 

Drop your rear end and put a solid piece of metal in place of the top rubber mount that controlls the front, rear movement of the diff. Than you'll be worring about snapping half- shalfs. We did it to our supercharged car, and the next weak point of the driveline was exposed.

 

you meen remove the bushings and add soild metal? keep me informed i like where this is going

 

any body else?

 

Do you have a TII or N/A?

 

why would you do this on anything except a drag strip car? even then...
there is a reason that rubber bushings are used stock. i am all for poly-urethane, because then at least you keep some of the rebound and movement characteristics...solid bushings with the stock drivetrain components is just asking for trouble...

may i inquire how much faster your 1/4 mile became with the solid component?

 

odds are its a bad diff mount, but look out, it could just be a worn out diff. i replaced my diff mount, only to learnt that my mount was fine, everything was up to spec, except ther was excesive play in the ring and pinion. if while you have the back of the car up in the air, you can turn the driveshaft ANY realy amount before either of the wheels start turning, your diff is shot.

it doesnt have to be puking gears or seasing etiher, 100k+miles of driving, especialy hard driving mixed in and it will just get sloppy over time.

when i get my hands back on my car im gonaa be swapping in a clutch type LSD diff from an s4 n/a. should help ALOT of problems that crappy diff is giving me.


the driving symptoms betwwen a busted mount and a worn diff are baisically identical, so just get under the car and check

 

Clutch type is the way to go.. I haven't heard anything good about the viscous type..

 

well the s5 n/a viscous type with the 4.3 ring gear from the gtus realy is the ultimate n/a diff to have, however they go for about $400, while a decent s4 diff is only like $100 or less depending on connections.

now 4.3 ring with a rebuilt or even aftermarket cluth lsd, THAT would be sweet, but whos got the 500-$1k that would cost?

 

The 4.10 TII clutch type diff is a pretty good diff from what I've read.

 

Supposedly a rear strut bar helps immensely on the fc's...

 

my set up on my n/a is this, tokico's illum, eibach springs, rear strut bar, with some nittos 555r's 225/50/16 , my best is a 2.1 60' with a 4500 clutch slip (my clutch is almost done). I am messing with the rear camber to try to hit 1.9.

 

I did it when my car was still N/A. I swapped a torsen LSD from a miata into a 4.3 GTUs rear end. Check out the archives...

 

allright i like the feed back ! thanks alot and no i haven't ran her yet i'd get a better launch if the rear didnt have a mind of its own thanks again i guess its down to the bushings.

 

ow, if you hit a 1.9 with a N/A, that'd be sweet..

 

strut bars maybe in the back?

 

ill check the diff for slop but there shouldn't be any i replaced it about 2 months ago. and i haven't had time to fix anything yet so the 1/4 mile hasn't improved,im afraid ill break something and it'll have to be put up on blocks again. i already had to change the rear diff and driveshaft but thank you guys for you help!

 

no the diff rocks back and forth when im gettin on it i don't think strut bars would help with that.

 

If the actual diff moves then why in the hell is everyone saying that it could be something other than bushings. That is the only thing. A worn diff wont rock back and forth. Sounds like a broken front diff mount to me. Check it out.

 

There are 3 solutions to this problem.

• competition front diff mount (polyurethane instead of rubber)
  I think Mazdatrix sells them. Supposedly very good for power adder cars but not enough for the torque of a V8.
  
• welded front diff mount
  I did this by simply "boxing" the factory mount with some 1/4" steel from Home Depot and a mig welder. Very effective and I don't care about the extra vibration because the whole car vibrates anyway.
  
• pinion snubber to keep front of diff from moving upwards
  Allows the factory diff mount to absorb the shock and vibration of a launch but won't let the front of the diff move up, so your pinion stays pointed where it's supposed to. Several of the folks on torquecentral.com have posted instructions and pics of this and have said it works great. I will be adding this when I put the new motor in, since it will have even more torque.