ack5252

You should contact the user s2kpuddydaddy on here, he is extremely knowledgeable on this topic and has built a TON of diffs for s2k owners on here using every type of gearset under the sun (4.10, 4.3, 4.44, 4.57, 4.77). I had him build me a 4.57 diff and look forward to installing it in a few weeks. I chose the 4.57 after talking with several people who indicated it gives a decent bump in acceleration without the super high revving nature of the 4.77. It is a Richmond gearset which is just as good in terms of quality as the j's racing unit, but for about $500 bux cheaper.

sro_alvaro

thanks man, i will definitely contact him! let me know for sure what you think about the 4.57, maybe u can pursued me into getting those lol
keep me updated!

ans2k

The 4.57 is pretty rare and I'm pretty sure no longer in production

sro_alvaro

hmmm... well i just bought my 2009 S2K!
couldnt be happier!

ack5252

Man your right I totally forgot about him telling me that. If I recall correctly though he had 1-2 more left after mine. Might be worth a shot?

ans2k

i do like my 4.44. i cant imagine what it would be like going back to stock. it gives that nice peppy-ness off the line. but it is not too much different than stock in terms of cruising rpm.

sro_alvaro

i think im going with the 4.77

http://www.streetfire.net/video/Tjs-...ome_170050.htm

Leviisbigred

i had 4.77s in my ap1 and i loved them, you dont need that for your ap2, get 4.44s , its the same as a ap1 with 4.77s. if you go 4.77s you will lose to much gearing and be like at 5k going 70mph in 6th lol 4.44s!

Rubn1out4GudLuk

"When" my diff goes I will have 4.30 gears put in...No boost in my future. From my research 4.30's won't be a burden on the fwy yet make the car a little peppier and more fun to drive.

Duke Togo

You just bought your car and your going to spend at least 1000 dollars to completely ruin it ?

First off the 4.57's are garbage that's why they arent being produced unless you like lots of gear whine, the ring and pinion doesn't have a proper fit. There are only 2 proper FD combos and possibly a 3rd - the 4.4, 4.77 and the 4.67 possibly. For your Ap2 you need to read the threads about mph/rpm in each gear. The 4.77's would make your car annoying at best, stick to the 4.4's The video you posted is for a completely different engine, transmission combo than yours. You need to understand the ap1 f20c engine and gearbox is not the same as your ap2 derived f22 engine and gearbox.

Also I am not sure why no one has brought this up but J's racing uses the Kia produced ring and pinions which you can buy for 270 on kia parts instead.