myslow1

Hi I am just curious if you can put an ap1 differential in an ap2 and what needs to be done to make it work. I came across a great price on a cryo treated ap1 diff with gears and would like to pick it up. I couldn't find any information on what would need to be done.... All I know is it is not a direct swap.


Thank you for any informaion,
Jason

ans2k

really? you couldn't find any info? wow i have seen posts like this is many times. try to do a better search. but basically they are not plug and play. the flanges on the ap1 and ap2 diffs are different. just need to swap your ap2 flange with the ap1 flange on the diff and you should be good to go. how do you do it? or how hard is it you may ask. search my friend.

Gernby

I realize this is not an answer to your questions, but you should really get an AP2 diff. An AP2 diff is probably going to be more reliable than an AP1 diff even if it is cryo treated. Gears are another thing you may want to reconsider. If you are only going to straight line race from a stop, or if you are going to daily drive it on surface streets (not the highway), then lower gears (numerically higher) will be fun. However, if you want to autocross or track the car, or drive it on the highway, you'll probably regret the gears.

Andrew Wojteczko

you need to swap the input flange on the diff, everything else should be the same.

Quivers

only take 1-2 minutes to swap the flange but as others are saying I wouldn't recommend it.

myslow1

thank you, but i have searched around enough and i really want gears lol! I drive my car around town and on the highway for about 15 minutes twice a week.

myslow1

why not?

Gernby

I just wanted to make sure you understood the trade-offs. I installed 4.77's in my AP1, and it was the most regrettable mod I ever did. I was never competitive with other stock S2000's again at the local autocrosses. I imagine this problem will be MUCH more significant on the AP2, since it already has lower gearing than the AP1s.

If you do it, make sure you use a great oil. like LE-1605, since the AP1 diffs supposedly don't have as good of a design as the AP2 diff.

myslow1

ok well I am still not finding all of this information that is on s2ki about swapping. I have read you need to swap flanges and i have read all you need is different bolts. Which one is it?

S2KPUDDYDAD

Send me a PM and I will send you directions on how to do the swap. You will need a new pinion nut along with the AP2 input flange.