I have done this "mod" but out of respect for TRE and others who do this I really can't go in to detail to much but I can say that it totally transforms the evo in to a rwd type of car with *** out drifting if you wanted to do it.

 

Oh no for sure dude - I did a lot of reading on it, it's an excellent mod for the Evo - I'm wondering if it's how the JDM Evo RS's rear differential performed from the factory. I think we're talking about different things here. But yea I've read tons of reviews on it, it works great - really transforms the Evo

But - the stock 8/9 rear diff is NOT the evo JDM rear diff (JDM evo RS's came with a mechanical 1.5 way instead of the AYC, but NOT the mechanical that the USDM cars came with).

 

I have never had a jdm rs diff apart so I can't really speak for that but I am pretty sure that they are configured in the way I am talking about in which this "mod" came about for the rally cars and can be applied to any street car.

I believe in the jdm rs cars they set the rear diff up this way from the factory since they don't have ayc.

 

Plus 1

 

the us diff is configured very poorly and has a weak loose lsd unit and in stock form is not even close to a 1.5 way.

 

Amen Close the thread

 

Exactly - it's NOT what the JDM RS gets, a really nice 1.5 way mechanical. I think the parts used in ours are sourced from Evo 4-6 mechanicals, NOT the new RS

 

I know the 2006 IX USDM rear 1.5 way LSD isn't "identical" to a JDM version, but for discussion purposes lets call the USDM rear diff a 1.5 way LSD just because that's how the USDM version was marketed - with that in mind, my question is: was the 2005 VIII USDM rear diff the same as the 2006 IX USDM "1.5 way" limited slip?
If 2005 USDM did have the same rear diff, was it the same in all USDM models (RS, SE, MR, GSR) or did some 2005 models have a non-LSD, open diff or some other diff?

 

when was it marketed that way? it's a modified version of an evo3, a 1 way, and not even assembled properly. To answer your question all of the rear differnetials 03-06 are the same, its the front that changed

check my sig a lot more info has changed since this thread

 

Thanks - by marketing I just mean US spec sheets, dealer talk, etc, they call the 2006 rear diff is a 1.5 way limited slip diff. I know the front diff changed from open to helical LSD in 2005, but I didn't know if the so called 2006 1.5 way LSD (or whatever it is) was used only in 2006, only in 2005-2006, or used all thru 2003-2006.

And it was used on all models, correct? Not just MR, or RS or something?

 

yep. most people upgrade it to a TRE 1.5 way or a Shep. Not a 1.5 way stock.