legacycentral bbs

well i ordred my twin turbo trannie to put in my car. however i was told by jeff denmeade last night that the final drive in that trannie is 4:11. is that right? does anyone know for sure? if so I gotta find out how to switch that over to 3:90. I dont want to go buy a rear diff thats 4:11, I dont mind cruising at 70mph and doing 3grand, but with 4:11 that will rise considerably. can anyone tell me if there is just one gear for final drive and which one it is so i can press it out and press the new one on?

thanks,
mike

That means that the front diff is also 4:11 and would have to be
changed. One thing to be careful about when switching rear diffs is
there are two different sizes of flanges on the diffs and they are
not really interchangable as the flange fits into the diff and
determines the position of the pinion gear.
AL (CO)
al@iwtu.net

There is a sticker on your transmission, near the starter. Find it and look up the number on this chart. It should be listed there.

http://www.rrunracing.com/Transmissions.htm

The 2nd flange size is the R180 or STI flanges. They require new half shafts and wheel bearings.
Mark

so what should i do, change out the ring gear and pinion gear of the rear diff so i keep the LSD and have 4:11 gears, or change out the pinion shaft on the lower gearset in the new trannie so i can drop in my 3:90 front diff? which would be easier/better/less money

4.11 open diff is easily available Automatic Legacy and the foresters. One advantage to this diff is the gears (esp 2nd and 3rd) are closer together. You loose a little top end speed however (If you usually go more then 200km/h...)
Mark