awesome feedback. I'll see if my Henry's Lap Timer can show similar gains at Big Willow. 1 second seems huge though. You didn't have newer tires or a tweaked tune that could contribute to that much gain?

 

Tune was the same as were the tires. my tire pressures were more in line with what I should have this time though. Weather was also around 10°C cooler. I'd say the diff accounted for a half-second or so.

 

Having just done this mod to the USDM rear end I have now fitted to my V first of all I would like to thank the OP for the information...the car is SOOO much nicer to drive than the old AYC unit, very predictable and the back end steps out a lot easier!

Also I can completely understand why they didnt do this from the factory...4 out of 5 people would have returned the car with warranty claims, its very noisy and clunky but thats what a mechanical diff is meant to sound like!

Most end consumers dont understand that

 

Thanks to the OP for figuring this out and everyone for commenting on it.
There will always be some noise from a properly working diff. I wonder what the difference in sound would be if you purchased all new plates and clutches and rebuilt it the right way vs rearranging preworn plates/clutches? Has anyone tried that?

Also, Lets say that you wanted to correct some of the understeer problem with these cars. Would just getting the ACD tuned have more of an effect then the rearranged plates? Does that shorten the life of the ACD unit? Not trying to highjack the thread but I was curious. Thanks in advance.

 

I had the same problem

 

Oops wrong thread sorry

 

one question here, how many plates/discs are there in factory diff ?
if take in account two spring plates(one on each side), in total 12 including them ?

as per manual:

sp.plate|plate|disc|plate|disc|plate|||||plate|disc|plate|disc|plate|sp.plate

correct ?

and when you get Wier 12 plate, you reuse factory spring plates? so you get 14 plates installed in total ?

 

Very good DIY. Subscribed

 

Anymore feedback from people who have rearranged their rear diff plates?

 

Still working great for me, the rearranged diff would clunk during slow, tight turns for the first 500-1000 miles or so, but now it's quiet. Using OEM fluid.

 

Are you not convinced it's awesome?

It's awesome.

If you've got the $$ to buy a fancier rear diff, that would be better - but for the price it is a great mod, for motorsports especially. For the street I would not bother.

 

Not sure my butt dyno can tell the difference, and I couldn't really measure on track performance because I changed too many things during my build at once. I don't have any clunking or any other daily driving negatives. Short of getting a bit dirty I don't see any reason, from my experience, not to do this mod.

Like they said above, the price is right!

 

You don't gain any power from this, so your butt dyno shouldn't feel any difference.

 

Yup, exactly, but several folks are commenting that they can feel the power delivery out of corners better to shoot them off of the apex. Your own laptime improvements are a good example. Did you feel a difference in the out of corner traction? If you got .5 a second or a full second in lap times it would be hard to feel in your butt dyno without your lap time data.

That is what I meant. My butt dyno didn't feel anything, (on or off track) AND I don't have lap times to prove anything for that mod specifically. Butt, it does make logical sense that its working better in this seemingly intended orientation of friction plates.

 

This is a driver mod. This has made my drive in the hills and mountains so much nicer and more calm. It's wierd, but the car rolls less too.

The downside though is that if you don't want to do 7-10k diff fluid changes, don't do this mod. My fluid gets beat fast. The last fluid change came out looking like metal soup. This mod makes the plates shed material, which is actually what a clutch diff does, hence the need for rebuilds.

I also get slight clunking in slow speed turns and doing a tight turn in a parking lot garners unusual stares because my tires will chirp. I have noticed that my rear tires are also wearing out faster. Just some negatives.