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jamesinger
09-02-2012, 02:05 PM
I blew up my EVO. It sounds more exciting than it actually was. Basically the motor and the trans were on their way out respectively at 93k of driving mostly in anger and stuff went wrong at BRP coming out of the esses. In any case, I am now looking over the complete car and one of the things that seems to be quite controversial when searching on the interwebz is the rear diff. mod for the USDM EVOs.

http://image.superstreetonline.com/f/9520567/p119425_large%2BMitsubishi_Lancer_Evolution_VII%2B Rear_Differential.jpg

To make a long story short, what I have ascertained through and exhaustive study of hardcore eT00nerz and actual real deal EVO specialists like the fine folks at RRE is that the USDM EVO came with a watered down version of the rear diff found on JDM EVOs. However, the diff is actually the same and it is fairly simple to "mod" the diff. back to its more drifto happy ass out Jeremy Clarkson test drive on youtubby self. I know RRE can do this, Mueller can do this, and there are some of places like TRE and Shep that you can send your rear diff. to that will do this. Last, on EVOm, there are even tutorials on how to do this...

SO, the question is for people WHO HAVE ACTUALLY DONE THIS, is it worth it? It seems like something I want to do BUT I have been told that some of the people on this forum that have done it (who will remain nameless until they come forward in an attempt to protect their reputations as bad ass drivers), have gone into the dirt at the track and have also had a lot of troubles keeping the car under control once the more RWD like characteristics come out.

Can anyone talk about their experience with this? Learning curve? Keep it USDM? Mod it? I'd like educated opinions and actual experience comments, which is why I did not ask on EVOm.

The last thing I will say about this is, I would rather run a stock rear sway bar or an upgraded one on the softest setting and let the diff do its job over putting a giant sway bar on there. That is just my opinion on that though.

Thank you.

Azian
09-02-2012, 02:14 PM
I've had this mod done with no additional plates added for about 8 months now. The learning curve is somewhat high in my opinion and it takes awhile to get used to. You can tinker with the suspension to try and make the car "balanced" and "neutral" but it takes quite a bit of fine tuning. It took about 4-6 track days to finally get my car to where I wanted it, which is neutral with very slight oversteer occasionally. Robi likes car that has quite a bit of oversteer but not all drivers will enjoy it as much as he does including myself. If you're interested in doing this you can give him or your suspension tuner of choice a call. Robi (aka Robispec) charges $350 for this service I believe. The effectiveness of this modification depends on many many many factors as well. For example, what shocks are on the car, spring rates, tires, alignment etc etc etc

Massimo Power
09-02-2012, 02:32 PM
Just doing the mod and leaving the car as it sits you will notice a lot of on throttle over-steering and even some at turn in. The suspension/alignment can be adjusted to help balance this out to your particular driving style and comfort without ruling out the mod. It will be a different car so it will take some different inputs and seat time but overall you should be extremely happy with the results once it is set up to your liking. The way Ben describes his setup as Neutral with a hint of over-steer (Usually on throttle) is exactly how most of our set ups end up. Setting up is definitely the key though, if you do not set it up to your liking you will most likely be doing more harm that good.

Azian
09-02-2012, 02:34 PM
Just doing the mod and leaving the car as it sits you will notice a lot of on throttle over-steering and even some at turn in. The suspension/alignment can be adjusted to help balance this out to your particular driving style and comfort without ruling out the mod. It will be a different car so it will take some different inputs and seat time but overall you should be extremely happy with the results once it is set up to your liking. The way Ben describes his setup as Neutral with a hint of over-steer (Usually on throttle) is exactly how most of our set ups end up. Setting up is definitely the key though, if you do not set it up to your liking you will most likely be doing more harm that good.
When he says "harm", he means you'll be scared as F**K to go fast in a turn because the car will get mad sideways, and therefore you won't push harder and will end up being slower :)

Massimo Power
09-02-2012, 02:40 PM
harm (härm)

Adjective:
Fearful; frightened.

1. To be scared as F**K to go fast in car turn because the car will get mad sideways, and therefore you won't push harder and will end up being slower

Synonyms:
frightened - afraid - fearful - apprehensive

jamesinger
09-02-2012, 03:16 PM
I think I will hold off and do this with my suspension when I get the chassis sorted rather than with the engine and trans work.

Azian
09-02-2012, 03:17 PM
harm (härm)

Adjective:
Fearful; frightened.

1. To be scared as F**K to go fast in car turn because the car will get mad sideways, and therefore you won't push harder and will end up being slower

Synonyms:
frightened - afraid - fearful - apprehensive
Me likessss :D

flyingscot
09-03-2012, 05:56 AM
i know your not talking about me James,i always go off track with the front end not the rear and the two biggest offs ive had i didnt have the diff mod lol

jamesinger
09-03-2012, 12:23 PM
i know your not talking about me James,i always go off track with the front end not the rear and the two biggest offs ive had i didnt have the diff mod lol


I won't verify that. I may or may not be referring to you. I actually forget whose names were specifically mentioned. My brain hard drive is full. I have to erase info. to add info.

(Ox)Evo9_
10-13-2012, 04:01 PM
I'm sure people that come from a rwd car to an Evo
Would enjoy this mod cuz they would be more used to
The tendencies of your rear end coming out

RallyBud
11-13-2012, 06:34 PM
I just did the rear diff mod today. I like the power oversteer characteristics already. I have a Progress rear sway bar coming in the mail. Does anyone have any suggestions which setting will work well with the rear diff mod?

Here is a video of me inducing some oversteer shortly after the install.
http://youtu.be/fdDX2_JyauU

Mike W
11-13-2012, 08:33 PM
It takes 3 minutes to change the rear sway bar adjustments. The correct adjustment is the one YOU like.

Mike W

TomsWarEvo
11-13-2012, 08:47 PM
Great info....=)