Yeah, I know all about the whine! I drove my EVO 6 hours down to Indianapolis and 6 hours back in a weekend - with solid mounted rear diff, no back seats, no sound deadening, sitting on aluminum Ultrashield seats. It sucked.

 

This will be interesting to see what TRE says, if the rear diff is even bad. You didn't try running the TRE diff with the stock mustache bar did you? I've had the 3 bolts that hold my BR MBE to the diff case back out a half turn or so - and when that happens the rear diff makes TONS more noise than it did before. I wonder if the clicking you heard could have been due to the broken MBE rather than the diff itself?? Keep us posted what TRE says. Thanks!

 

I have to agree with EVOlutionary, I don't see how a broken mount would break the diff.

Maybe wear out the rear u-joint in the driveshaft sooner than later, but I can't see it harming the diff.

I would like to hear the outcome, always good to learn something new.

 

My diff is on its way to Shep right now. I'm both happy and sorry to say that its effects will be a little trickier to identify quickly because I also added new coilovers and a Quaife in front at the same time I did take the car for a quick spin with just the coilovers and Quaife as it is right now without the rear diff upgrade, but it was just on the street so I didn't push it to the limits yet.

 

^ find an empty parking lot to use as a skidpad.

l8r)

 

i think you will notice a difference - those other mods dont force the rear end to come out on power like the rear diff will!

 

Once it's been smogged and registered it in CA, it's on! Hopefully one with cones too.

I sure hope so, I have wanted to do this for about three years. I just want to change the style of driving I was forced to develop around the open rear diff and last suspension just to keep the car going where I wanted, if that makes any sense.

I also need to remember to put the stock rear back bar on first. I think the 25mm bar on there right now is going to be way excessive, especially with 700-800lb springs in back. Too big a rear bar has proven to be downright dangerous at the limit if you're sliding at all in my experience. I just want to dial the oversteer in with throttle, not the damn lift, pushing and plowing! IMO you only have a few relatively fast ways to drive with that understeer, and I don't really care for any of them. So I'm really excited to find out.

 

I just did my first track day with my TRE Max Lock rear diff. Overall, I'm extremely pleased with it. It allowed the car to rotate much better under power and I was even able to get a little power oversteer with it, although it is still nothing like a RWD car. I have the stock ACD flash and I feel like the car could really benefit from the Gruppe-S flash, which I plan to do soon. I felt like I was fighting the ACD a bit, having to mash the gas a little earlier than I needed to just to get the diff to engage, as I was getting quite a bit of understeer on corner entry and mid corner. I feel like a more aggressive ACD flash could really help this issue. However, as far as corner exit goes, the car behaved great, and I definitely recommend this diff to anyone and everyone!

 

littletimmy, alignment settings? did you change them with the new diff? I found a small change in settings was required to maximize the diff upgrade.

 

Unchanged so far, -1.5 all around with zero toe. Planning to up the front camber a bit, it was still understeering quite a bit on corner entry and I think that will help. Not ready for any serious camber yet as it's my DD.

 

Any chance of adding some front caster? that would definitely help as well, and for a DD it will not give you that high static -3 degrees type camber for DD.. Just a friendly thought.

 

Yeah that's something I might be looking into as well. I wonder how it might affect straight line stability and corner entry\exit with the axis change.

 

I have the Perrins PSRS, and the added caster did not affect straight line stability of braking stability. It does feel ... different. I have a hard time putting the steering feel into words - for example with the added caster the car seems to tramline less, but when it does, it wanders more than before. Hope that makes sense.

l8r)

 

Lud- I would say the steering feels heavy, there is no positive zero position (straight) that it snaps back to after a turn or rotating the wheel.. if you turn, be ready to turn the wheel back to straight, as it feels heavy for lack of a better term, and seemingly stays where you turn it while in motion. Clear as mud for folks now...

 

This was my first season running an Evo. When I bought the car it had a TRE 1 way upgrade already done to it.
The diff definately works (I can hear it working), but I still fought slight understeer all season long from turn in to mid corner when getting back into the gas.
It seems that most people are running the 1.5 way for road coarse applications.

Has anyone ran both a 1 way and a 1.5 way to give some feedback on how the difference between the two impacts the handling of the car?