im swapping a dohc zc into an 89 civic 4 door and was wondering if i had to use the transaxle from the zc or the d15?

 

Your choice.
Zc, Si, Dx... all 'L3' tranny will bolt up to the block.

ZC tranny will use different axles than your stock ones.
All the other trannys can accept your stock axles.

 

use the dohc zc tranny for the best results it is as close to a b16 tranny you can get when it comes to d series trannys just get the axles from the 89 integra.thats three things the driver axle and half shaft and passenger side axle. good luck

 

the 86-89 Integra intermediate shaft will not work with a ZC engine - it has a different bolt pattern where it bolts to the block - the 86-89 Integra axles are too short - to use the ZC transmission, you need the ZC intermediate shaft (only ZC will work) and 90-93 Integra axles

 

^^^^
correct! People used to use one 86~89 and then the other was some hard to find axle off a prelude.

 

will 89 honda prelude axles work?

 

if you wanna save a little gas by having lower rpms on higher gears i would use an si transmission from 88-91 civic/crx. that way you dont have to worry about looking for the right axles that would fit on your zc transmission. plus you can use any year d-series axles from 88-00 civics.

right now im using 95 civic axles on my 89 crx with an si transmission.

and btw the dohc zc transmission have shorter gears than the si transmissions, itll save you some gas the long run.
[the smaller the number the longer the gear]

ZC DOHC
1st - 3.250
2nd - 1.944
3rd - 1.346
4th - 1.033
5th - 0.878
Rev. - 3.153
Final - 3.888

Si
1st - 3.250
2nd - 1.894
3rd - 1.259
4th - 0.937
5th - 0.771
Rev. - 3.153
Final - 4.250

i believe this would be the optimum for dohc zc's unless if your zc transmission comes with an untra rare lsd.