Andrie

The final drive on AP1 transmission is 1.16. Rear end is 4.1. Effective final drive is 4.756
The final drive on AP2 transmission is 1.208. Rear end is 4.1. Effective final drive is 4.953
The final drive on AP1 transmission is 1.16. Rear end is 4.4. Effective final drive is 5.104

AP1 gears
1st: 3.133 x 4.756 = 14.9 actual gear, replace 4.756 with 5.104 for 4.4 rear end = 15.99
2nd: 2.045 x 4.756 = 9.73 actual gear, replace 4.756 with 5.104 for 4.4 rear end = 10.44
3rd: 1.481 x 4.756 = 7.04 actual gear, replace 4.756 with 5.104 for 4.4 rear end = 7.56
4th: 1.161 x 4.756 = 5.52 actual gear, replace 4.756 with 5.104 for 4.4 rear end = 5.93
5th: 0.970 x 4.756 = 4.61 actual gear, replace 4.756 with 5.104 for 4.4 rear end = 4.95
6th: 0.810 x 4.756 = 3.85 actual gear, replace 4.756 with 5.104 for 4.4 rear end = 4.13

Compare with AP2 transmission
1st: 3.133 x 4.953 = 15.52
2nd: 2.045 x 4.953 = 10.13
3rd: 1.481 x 4.953 = 7.34
4th: 1.161 x 4.953 = 5.75
5th: 0.943 x 4.953 = 4.67
6th: 0.763 x 4.953 = 3.88

You see, the gap from 4th to 5th, and 5th to 6th is smaller on AP1 trans. This keeps the rpm up and put it in stronger power band for racing. AP2 trans is more for hwy cruising.

Andrie

This is not correct. See my post above about actual gearing. 5th and 6th gearing on AP1 and AP2 are actually very similar, AP2 is slightly shorter.
So if you replace AP1 transmission with AP2 transmission, you will have shorter gears from 1st to 4th, similar with AP1 running 4.4 rear end. However, your 5th and 6th will be really close to stock AP1 gearing running 4.1 rear end.

chilipie

Hey guys thanks for the information. My 00 is my dd and its has 117*** miles on the original clutch. Never been replaced. I think its time. Also my transmission rattles like crazy when cold then dies down when it heats up. A shop told me that it might a bearing of some sort. These are the reasons why im looking to replace my ap1 transmission with an ap2 transmission. Also to gain alittle mpg.

Voodoo_S2K

Your clutch could still have plenty of miles on it. I'm coming up on 180k on mine .

Andrie

To fit, AP2 transmission on AP1, you need to change the output flange. The AP2 has bigger output flange.
However, as I said, for performance purposes, I think AP1 transmission with 4.4 rear end is better than AP2 transmission. If you're running AP1 engine, I think AP1 transmission with 4.7 rear end is even better, since you have 9000 rpm.

slightly2ned

I ran 4.77 on a built diff in my AP1 and felt the gears were too short; I was constantly shifting mid corner or negotiating the speed to accomodate for the shifts. Thats just my preference though. I did find going from stop light to stop light to be fun & the car was definitely quicker in acceleration & had better torque down low for obvious reasons. Eventually, I got tired of the setup & swapped it out back for stock. One other con on my part was that I lost MPG with that setup as well; cruising on the freeway in 6th was hurt, lol - had to reduce cruising speeds which I guess is a good thing.

Since my tranny is getting a little older, I do like the idea of having a fresher tranny with less miles along with the additional carbon synchros vs a 4.44 diff. The cool thing about the diff is the install can be much easier & less involved vs installing a tranny - this depends though if the diff is freshly built & needs to be broken in or used & ready for bolt on. The diff will need an output flange swap as well just like the tranny depending on what version car you got this from vs your own.

iDashX

i thought you need an ap2 propeller shaft.

Andrie

You need AP2 output flange and bolts.

Or AP2 propeller shaft and Diff input flange and bolts.

The first choice is cheaper. I do have AP2 prop shaft for sale if you decide to go that route.

dagle

I have a 2.2L F20 (F22C1 crank + f20 rods+pistons), AP1 tranny, and a J's 4.4 gear in the rear diff, and this setup is NOT fun on the highway. Corrected speed (GPS) I'm at ~3900-4000RPM at 65MPH and over 4k at 70mph... I'm running 255/40/17R 225/40/17F for reference. For my past couple of other s2k's it was much more tame to cruise around

To cruise at 80-85 it's at 4500-4600RPM which sounds like an army of bumblebees

AP2 tranny + AP2 diff all the way

iDashX

I was gonna recommend yours