91 hf to si (d16a6) swap

[rextec]

im doing this swap for a friend and we already have the ecu and the si motor. is there any wiring changes? we are going to be running a 89 pm6 ecu with the 91 crx, will they be compatible?
thanks

 

[MaaseyRacer]

The HF is already MPFI, so wiring should not have to be changed, when I did an MPFI swap on my DX, I looked up SI ecu wiring a haynes manual, and it listed the HF and SI in one diagram so who know that book does suck. So you might want to find an HF or SI ecu diagram. Are you keeping the HF tranny??? if so then you should not need new axels or hubs. if you put a DX, LX, SI, or EX tranny on then you will need new hubs, and axels. other than that it should be a straight forward swap.

 

[dirty91crx]

hehehe bet you didnt know L3 tranny differential gears have the same spline count through dx, lx, hf, si, ex...odd ball was the zc tranny having to use teg axles...i know this damnit...lol im runnin an si diff with hf axles. the 89-91 pm6 are compatible...im runnin either (depends on use of car) pg7 or an 89 pm6. no rewiring having to be done on the 91 hf body. your also going to have to use the d15 driver motor mount brackets as the z6 bracket is a lil off. there are going to be a few wires needing to be lengthend such as the CTS as its on the z6 thermo housing compared the dx on back of block.

 

[evoracer03]

Originally posted by dirty91crx@Sep 20 2003, 02:39 AM
hehehe bet you didnt know L3 tranny differential gears have the same spline count through dx, lx, hf, si, ex...odd ball was the zc tranny having to use teg axles...i know this damnit...lol im runnin an si diff with hf axles. the 89-91 pm6 are compatible...im runnin either (depends on use of car) pg7 or an 89 pm6. no rewiring having to be done on the 91 hf body. your also going to have to use the d15 driver motor mount brackets as the z6 bracket is a lil off. there are going to be a few wires needing to be lengthend such as the CTS as its on the z6 thermo housing compared the dx on back of block.

dont forget the 88 had a different spline count than the rest of them though, and if youre doing the swap with an a6 you wont have to change any of the mounts. it should be all just plug and play.

 

[rextec]

thanks!

 

[dirty91crx]

dont forget the 88 had a different spline count than the rest of them though, and if youre doing the swap with an a6 you wont have to change any of the mounts. it should be all just plug and play.

forgot to mention that...good lookin out. and yes its plug and play!

 

[crx]

what wire harness are you using? i had to use a si harness with mine so i have to move around some wires etc. e-mail me at crx_dx@hotmail.com and tell me what your using, have wiring diagrams and stuff

-joseph

 

[biglee414]

i hate to thread jack, but what you are saying is that si adn hf have basically the same axels, so if i were to put an 90 si tranny in my 90 hf i wouldn't have to change out the axels, and hubs? this is contrary to everything i was ever told!

 

[jlicrx]

Originally posted by biglee414@Sep 21 2003, 07:11 PM
i hate to thread jack, but what you are saying is that si adn hf have basically the same axels, so if i were to put an 90 si tranny in my 90 hf i wouldn't have to change out the axels, and hubs? this is contrary to everything i was ever told!

all 2nd gen CRX and 4th Gen Civic have the same CV joints at the transmission end - the difference is at the hub end - the CRX HF and Civic STD have smaller splines at the hub - as long as you keep the axles for your car, be it HF, DX, Si, etc. you can swap any L3 transmission except for the ZC which uses different axles (90-93 Integra) and requires DX or Si hubs

 

[rextec]

what about the emissions control box on the HF will that swap over also, or will i have to get the evap purge from the si/dx?

 

[evoracer03]

Originally posted by jlicrx+Sep 22 2003, 02:14 AM-->

biglee414

@Sep 21 2003, 07:11 PM
i hate to thread jack, but what you are saying is that si adn hf have basically the same axels, so if i were to put an 90 si tranny in my 90 hf i wouldn't have to change out the axels, and hubs?  this is contrary to everything i was ever told!

all 2nd gen CRX and 4th Gen Civic have the same CV joints at the transmission end - the difference is at the hub end - the CRX HF and Civic STD have smaller splines at the hub - as long as you keep the axles for your car, be it HF, DX, Si, etc. you can swap any L3 transmission except for the ZC which uses different axles (90-93 Integra) and requires DX or Si hubs

once again, i have to mention that the 88 tranny has smaller splines on the tranny side (cant remember the exact count) but anyway the emissions control box should work just fine... if you dont need a smog cert you only need to hook up th map sensor and you can just plug the rest.

 

[zc_hatch]

zc uses 88 and 89 tranny, its a d-series, a 90-93 integra tranny is for a b series. wont work with each other, the only wiring you have to do is sxtend a few wires as already stated. also dont want to use hf exhaust manifold if you have an si, i think that is common sense.
jones

 

[Jeef]

Originally posted by zc_hatch@Sep 23 2003, 12:14 AM
zc uses 88 and 89 tranny, its a d-series, a 90-93 integra tranny is for a b series. wont work with each other, the only wiring you have to do is sxtend a few wires as already stated. also dont want to use hf exhaust manifold if you have an si, i think that is common sense.
jones

The zc use part of the 90-93 teg axles, as they zc has equal length shafts. A standard l3 usdm does not have equal length shafts.

 

[daidilus]

it is called an intermediate shaft