Originally Posted by mass-hole
Here its saying that the front diff is a 3.9 final drive and the rear is a 3.545 final drive so the center diff has to do some kind of manipulation. It doesnt go into detail on the year but i thought that some years of STis had a 3.9 rear as well.
I thought the spec.b was a 3.9 rear.
That was one of the main reasons I was curious. I wasn't sure if you'd be able to simply swap the transfer gears from the spec.B center to the DCCD center to maintain the 1:1. 2004-2005 STI 6MTs are 1:1 anyhow, but if you get a 2006+ (which I would prefer for the mechanical center when open) you need to do something about the1.1:1.
Of course, you could alternately replace the R&P on the rear diff and use 3.54 I guess.