can I put a y1 lsd into a s1 tranny. reason asking i have the s1 and can get the y1 lsd for a preety good price and not sure if it will work

 

if the Y1 LSD has 10 ring rear bolts, yes......

 

should work...the ring and pinion gears in a ys1 LS tranny are the same as the y1 b16 tranny (4.26 JDM b16 crx sir)....s1 is a 4.40 (JDM b16 xsi integra)

 

so your saying 4.266 FD and 4.400 FD are the same.........

I beg to differ.........

 

my bad i edited i may have the s1 and y1 backwards on the FDs but i think that's right....however i do believe all the b series cable tranny diffs and FDs are innerchangeable...i changed the final drive and diff in my b16 from a 4.26 to a 4.40....bolted up fine....

 

Yes, the countershafts have the same number of teeth (15) for both the 4.266 and the 4.400 FD.

 

same number of teeth, but different parts.

the teeth are cut at a slightly different angle and they won't mesh.

Same thing goes with the 70/16 4.25 and 71/16 4.437 D series FD's, the parts are different.

 

How much different?

 

enough the gears would be wiped out in 2-3 miles.........

 

what is the final drive on a j1? same with shorter gears? all my spare s1 and a1 trannies are 4.40. guess i'll have to take my j1 apart to count the fd teeth