This!

I think alot of issues occur with the driveline of these cars with stock gearing, wheelhop,HD clutch and aggressive launching. You can't expect things to live if they are loaded/unloaded with power.

 

I purchased a second t-case out of an EVO 9 with the intention of swapping my open front diff once I blew it up drag racing. Funny thing is... I never did lol. I used to launch with the 2 step at 6200rpm. Tons of 1/8th mile runs. Never had the car over 450whp or 400ftlbs of torque though.

 

Check out this vid:
Quote from the Video Maker:
I always thought that it would lock and both wheels would spin with equal amount of torque when under conditions of one wheel traction and the other zero traction. Either there is something wrong with his Wavetrac or we now know it doesnt lock or come any where near equal amount of torque when one wheel has traction and the other has zero traction.

 

Couldn't feel a difference on the street, but at the autocross it felt great. There is this smoothness about the mid corner and corner exit now. Even if I initiate a jerky transition the car just progressively settles into the direction I'm pointed at. It's sort of a gliding feeling, as if you have more slip angle to work with.

No improvement with corner entry understeer though, that part is up to you.

 

Probably something wrong with that guys diff. Pick the the "how it's different" link at the top of the page:


http://www.wavetrac.net/technical.htm

 

Agree.

 

This. If you need a new front diff then the wavetrac is worth considering. But if your stock helical diff is not broke, spend your money on something that will have a bigger impact on handling. Like a TRE max lock (which will reduce understeer), or a nice set of coilovers.

 

I'm becoming somewhat fascinated with the general strong interest in increasing the rear diff coupling. It feels to me that balance would be better addressed by first going with coilovers and alignment. Logical next step would be upgrading front and rear diffs simultaneously to maintain balance. But this is from a cornering perspective, and I think the OP was looking at front diff options from a drag racing perspective.

 

The stock limited slip in the 05-06 is good from a functional standpoint as an LSD. It just doesn't have the strength for drag racing.

 

I just think you would be hard pressed to 'feel' (or see appreciable improvements in lap times), by replacing the front helical diff with a wavetrac. If someone has data proving me wrong I would love to see it.

I have personally used a TRE max lock, and while I found it a bit noisy, it works. You can feel it working. The car would rotate MUCH better on power. I would even go so far as to say you could induce oversteer if you wanted.

I agree with you on balance, but I have not found a set of coilovers or alignment specs that will eliminate the Evos tendency to understeer.