Rear Diff Options - Power Oversteer Found Here
Newbie
Joined: Aug 2007
Posts: 21
Likes: 0
From: Calgary, AB, Canada
Marshall,
I've had that very same thing happen a couple times on my 03 w/viscous center. Not sure it's ACD related. Sure feels crazy.
Also totally agree on the front inside wheelspin. It definitely occurs. If you watch video around 35 seconds you can hear the rev limiter pop, then go silent and pop again. The trend with short stroke dampers certainly doesn't help the situation. I have spoken with Jon @ TRE about front diffs. What he basically said was that the clutch type front diffs are fantastic in the dirt where the lockup is tolerable on turn in and totally necessary on exit. When used on asphalt they don't work very well. He's had customer's swap back to torsen (OEM, Quaife, etc) from clutch type. I was really interested in trying one but my car has been sitting for a year now.
http://holunfie.blogspot.com/2007/04...-diff-and.html
All,
As for the GSC 40/60 Center Diff I have one. With the lower power levels on my car (298 hp/320tq, dynojet) it was very subtle, but did help the car to rotate. There was a more profound effect with the TRE rear diff though once I added it. Everyone I knew that ran one liked it. Don't know of anyone running one with ACD though.
If you're interested pics are here:
http://bp1.blogger.com/_rOf08BWxyfo/...h/100_3575.JPG
John
I've had that very same thing happen a couple times on my 03 w/viscous center. Not sure it's ACD related. Sure feels crazy.
Also totally agree on the front inside wheelspin. It definitely occurs. If you watch video around 35 seconds you can hear the rev limiter pop, then go silent and pop again. The trend with short stroke dampers certainly doesn't help the situation. I have spoken with Jon @ TRE about front diffs. What he basically said was that the clutch type front diffs are fantastic in the dirt where the lockup is tolerable on turn in and totally necessary on exit. When used on asphalt they don't work very well. He's had customer's swap back to torsen (OEM, Quaife, etc) from clutch type. I was really interested in trying one but my car has been sitting for a year now.
http://holunfie.blogspot.com/2007/04...-diff-and.html
All,
As for the GSC 40/60 Center Diff I have one. With the lower power levels on my car (298 hp/320tq, dynojet) it was very subtle, but did help the car to rotate. There was a more profound effect with the TRE rear diff though once I added it. Everyone I knew that ran one liked it. Don't know of anyone running one with ACD though.
If you're interested pics are here:
http://bp1.blogger.com/_rOf08BWxyfo/...h/100_3575.JPG
John
I assume you kept the Viscous coupler? As far as I know the Evo's centre locker is no co-located with the diff, and that one has a choice of keeping or tossing ACD/Viscous even with centre differential swaps - unlike the Subaru guys.\
EDIT:
Nevermind, I saw that you did keep it. Perhaps that is why the difference was subtle. Nonetheless, that is probably a good choice since an open center diff (albeit, consistently transferring power 60% to the rears in all conditions) could be troublesome in low traction situations.
Last edited by randedge; Oct 7, 2012 at 03:10 PM.
bump! looking into if i should get the cusco rear diff!? wanting to upgrade the car handling wise trying to see if this is a good choice and still being able to daily it at times?!Don't see any negatives, if the car tracks out better and *** end comes around smoother/easier then its worth it. Correct me if im wrong please ha.
bump! looking into if i should get the cusco rear diff!? wanting to upgrade the car handling wise trying to see if this is a good choice and still being able to daily it at times?!Don't see any negatives, if the car tracks out better and *** end comes around smoother/easier then its worth it. Correct me if im wrong please ha.
Jon will work with you every step of the way, you have options when having TRE build you a diff unlike Cusco, you can send in a core to save money and Jon personally hand builds and measures them to his race level tolerances.
one great point about jon@tre, he doesn't just build his own - he shimmed and treated my cusco, with his custom cusco hd side cover and all the trimmings too.
he is really the man when it comes to this stuff
he is really the man when it comes to this stuff
Evolved Member
Joined: Jul 2003
Posts: 638
Likes: 7
Finally got my Max-lock from Jon @ TRE installed in my Evo IX. Car is set up with Robispec springs on Bilsteins and an ACD tuning reflash from Matthew Manke. There are some bushings in the equation as well.
All modifications were important for the car to make it what it is now. ACD remapping took the dreaded long sweeper understeer out and improved steering response. Robispec springs removed the high speed floatiness on the front end. But the TRE differential in combination with the other changes really transformed the car dynamically.
The car can now be steered on the throttle and I can get on the throttle much earlier in a given turn. It feels more like a RWD car now. Suspension/chassis set-up feels perfect now.
Of all modifications, the TRE diff certainly has put put the biggest grin on my face
And BTW there is no need for a bigger rear sway bar anymore that decreases traction in the rear and increases rear wheel lift.
All modifications were important for the car to make it what it is now. ACD remapping took the dreaded long sweeper understeer out and improved steering response. Robispec springs removed the high speed floatiness on the front end. But the TRE differential in combination with the other changes really transformed the car dynamically.
The car can now be steered on the throttle and I can get on the throttle much earlier in a given turn. It feels more like a RWD car now. Suspension/chassis set-up feels perfect now.
Of all modifications, the TRE diff certainly has put put the biggest grin on my face
And BTW there is no need for a bigger rear sway bar anymore that decreases traction in the rear and increases rear wheel lift.
