I'm writing this for those of you thinking about upgrading the LSD in your FD on a budget and not wanting to pay the $800+ price tag on an aftermarket unit (Kazz/Quaife).

I plan on putting somewhere around 450rwhp/400rwtq down when my car is done (Jan. '05 goal) and know that the stock FD Torsen is a weak link when pushing the envelope. I've heard about countless cars breaking them at the strip... even ones with only bolt ons (exhaust/intake and stock turbo).

I didn't want to spend the money for a KAZZ so I had researched and found that the S4 Turbo 2 LSD was a good option since it was the clutch pack style and known to be a strong unit.

I was lucky enuf to be able to do a straight up trade with a board member for my Torsen. After emailing a few others about installing this unit into the FD carrier all the replies I got back were just remove the old one... and install the new one. Of the 3 people I asked none of them went to a shop to have the lash checked or even thought about doing it.

Well I certainly wanted it checked so I went to a well known diff shop and brought them the empty FD carrier and the T2 LSD and told them what I wanted. I said I simply wanted the lash checked and it should be easy pacheesy. I didn't pull the pinion gear or do anything other than pull the stock Torsen out of the housing.

Well I return the next day and he said it wasn't a walk in the park. Upon installing the LSD with the existing 3:90 FD gear he said the lash was so far off he couldn't even get a reading. He said he had to shim the pinion gear in order to get it right and gave it a clean bill of health after that. He only charged me $125 for all this which I thought was fair at $85/hr. The guy also works on bus/Caterpillar rear ends and I saw ring gears in there as big as a small hoola hoop!

So to those of you that plan to do this upgrade I would recommend having the lash checked by a professional. My guy said it would've lasted a matter of miles before chewing itself up into worthless bits.

I'm building a road race car that I hope can run 10's n/a at close to 130mph on drag tires. With a 150hp NOS shot I hope to be in the 9's. We'll see how the T2 LSD holds up. I hope to weigh 2900lbs with driver or less.

Anyone want to donate some used FD stock halfshafts for testing? Or have a good deal on some 300M axles .

-GNX7

 

I put mine together and set the backlash wrong. When you are doing the swapbuy a new pinion collar. They are one use only, and i put about 300 miles on the diff with crappy backlash. You can hear it wine and clunk. I need to take it back apart again and install a new pinion collar...

 

Good info Mark. Mark, being from the domestic end of things, any thoughts on shops that might make some custom axles for my FC at less than the ~700.00 wanted for 300M, if I can even find them?

 

Carl- I wouldn't have any good leads. Unless you plan on making them in volume.... $700 is pretty much what you are looking at I'd bet. Call RX-7store or talk to Cris "Speed" Anderson in FL (Orlando area I believe).

You don't plan on drag racing anyway. Why not just have a bunch of stock T2 halfshafts? You haven't broken one yet have you?

-GNX7

 

No, and I do not plan on DR, so we shall see.

 

I can't believe anybody would swap the diff out of a pumpkin and not have the lash checked. Heck, you're supposed to do it even if replacing with the same type of diff!

 

Mark,
Glad to hear that everything went well. I'm lovin the Torsen. I can get the rear to do exactly what I want now. I can place it almost perfect.
I paid about $250 for my guy to set the lash. But I guess thats the difference lbetween living in CA and CT. Here good shops are hard to find.
peace,
-a

 

Sunshine- thanks again for swapping diffs with me. Worked out great for both of us. I hope mine lasts and works well like yours.

Just picked up an LS1 motor today . 23K miles complete with wiring harness/computer for $2K! Soooooo stoked.

-Mark

 

Mark, going to JGTC? Gimme a call

 

awesome, keep us updated on the progress, that sounds like a great deal on a LS1.

 

.... actually got it for $1500 since he couldn't find the computer for it

Very very happy.

-Mark