I have an '84 GSL-SE that I use in club road racing events, and I'm recently noticing wheelspin on the inside wheel exiting corners. I suspect my original LSD with 180K miles on it is ailing. The two options I see are 1) rebuild my OEM friction unit for $?? or 2) use the Miata Torsen unit for approx. $640.

Any comments, first hand experience, pricing info for either option, etc. would be helpful.

 

Elwood,

Personally, I would rebuild the LSD.

The Miata Torsen is a nice piece to have during a rain race, but the worm gears generate a ton of heat and driveline restriction. On a dry track, I'd much rather have the LSD in my racecar.

The bonus is that it's cheaper to rebuild your LSD than to spend the $600+ on the Torsen.

 

my dads car's LSD was just rebuilt and it is seriously almost a locked diff. even with the redline LSD application fluid, its TIGHT. go with the rebuild

 

Thanks for the advice. How much do rebuilds cost? I've rebuilt engines, including the 13B in my car -- how difficult is a differential? Do I need special tools?

I remember reading that the pinion to ring gear engagement pattern was crucial, but do I really need to alter this relationship if I'm changing the friction packs?

 

Rebuilding a diff is a lot easier than doing a motor. You need to make sure the gears align and mesh properly, and you need a measuring device so you can set and check the backlash according to spec. Other than that, it 's a piece of cake. Make sure you buy a new crush tube and torque everything to specs. You're looking at less than $100 in parts and an hour's work (once the pumpkin is out of the car). for racing purposes, make sure you buy the over-sized friction plate from Mazdaspeed. It tightens everything up nicely.

 

im not sure how much it cost for it on the race car... cuz the price included and engine rebuild and oil cooler and oil line repair.

 

Thanks again. It looks like I'll be doing it myself. I'll let you know how it works out.