Originally Posted by deylag

I have heard good things about this mod. I am trying to make the decision whether to do this or get a Cusco Rear Differential. I want to do it right the first time. I want to get the diff that gives the maximum lock and performance.

Originally Posted by WeirPerformance

I thought I would post up some usefull info here on plate type LSD units. There seems to be some confusion about 1 way, 1.5 way and 2 way settings. These settings have absolutely nothing to do with the clutch plates or how many plates you have in the LSD. The pressure rings inside the LSD unit dictate which setting the LSD will be. Here is how the different settings theoreticaly work:

1 way = full lock on accel only, open on coast
1.5 way = full lock on accel, half lock on coast
2 way = full lock on both accel and coast

The OEM Evo LSD is designed as a 1 way LSD. Adding plates to the LSD does not change the LSD to a 1.5 way unit. In order to change the LSD into a 1.5 way unit, the pressure ring must be machined to change the angle on the coast side of ring. Once this is done the LSD unit is a 1.5 way and cannot be changed back to a 1 way. The change is permanent.

We are working on fixturing to machine the pressure rings for 1.5 way operation as some of our customers have been requesting it. Once we have this done we will post pricing on our website, Thanks.

Originally Posted by son of krypton

Review: Weir Performance Maxgrip LSD Kit

It is no secret that our Evos came to the US with an improper rear differential setup. Most of us have experienced severe understeer and pushing effect during corner exit. There has also been extensive information sharing about correcting our rear differentials, primarily through sending our cores to a company and purchasing the upgrade https://www.evolutionm.net/forums/ev...ound-here.html. However, I wanted to have the performance benefits of a 12-plate rear differential upgrade without sending in my core and having downtime while my daily driven Evo was up on jack stands. Most importantly, I wanted it at a fraction of the cost! Weir Performance offered the Maxgrip LSD kit for the individuals wanting improved performance out of their rear differential. My autocross comrades and I got together one Sunday and performed the upgrade in a true, grassroots, and “Do-It-Yourself” manner.

My rear differential was in good condition to start. The rear differential has withstood over 113k miles of commuting, spirited drives, and of course, autox. The following link(s) will take you through the removal of the rear differential and assembly of the Weir Performance Maxgrip LSD Kit:

https://www.evolutionm.net/forums/ev...tial-diff.html

https://www.evolutionm.net/forums/ev...rear-diff.html

Suspension Setup:
Fortune Auto 500 Series Coilovers 12kg front/15kg rear with 4kg helper springs
Front Camber—3.5* Rear Camber—1.5* Toe—0* all around
Whiteline Rear Sway Bar—full soft setting
BBS MR wheels wrapped with 255/40 Hankook R-S3’s

Before the Weir Performance Maxgrip LSD Kit:

Exiting corners, I would experience understeer, having to feather the throttle. Trying to force the steering wheel would be futile, as the car would continue to push and tires squeal. If a descent straight away were ahead, I would be losing valuable time due to the inability to get on the throttle sooner. Or worse, the understeer would knock me off my line and affect how I reacted to the remainder of the course, and essentially be playing catch-up. I’ve tinkered with tire pressures and was on the medium setting of my rear sway bar and still would experience considerable understeer, pushing out of corners and unable to get on the throttle.

After the Weir Performance Maxgrip LSD kit:

Right after installation, I drove around in a parking lot, performing several figure 8’s. I then started to get a little antsy and took some tight turns in the parking lot while adding boost. Wow . . .the rear tires started spinning their wheels and the evo was suddenly in oversteer!

I had an autox event Sunday, 7/31, and wanted to put it through a more appropriate test suited for our cars and the rear diff upgrade. Holy cow, oversteer came on command!! Gradual and precise throttle, coupled with appropriate countersteer enabled me to be much faster coming out of corners. I took a long sweeping turn and was able to apply just enough throttle and countersteer to remain on my line and mash the throttle once I straightened out. Be warned though, it will take a bit of getting used to gradually getting on the throttle and not stabbing it. Before, I tried getting on the throttle and would only keep pushing outward. Today, I tried the same approach and spun out! So, practice is definitely needed to get that balance of throttle and countersteer. Damn it was fun, though, even when I had too much oversteer!

Bottom Line:
For those wanting more performance out of their Evo in the area of handling and achieving oversteer to power through corner exiting, the Maxgrip LSD Kit by Weir Performance is a worthy solution at a very affordable price. Most people who track or autox here may or may not be all out gear-heads; however, the procedure to perform the upgrade yourself is well within the individual willing to perform a DIY. Most importantly, you will be able to achieve upgraded rear differential performance compared to other name brand rear differential units without the downtime and at a fraction of the cost. Please keep in mind, I am in no way refuting the efforts and detail other companies have put toward their rear differential units. I am reporting the comparative performance observation of the Maxgrip LSD Kit and increased oversteer that is also claimed by other companies.