Ok I'm gonna have my 90 engine swapped with a 91 DE. I was wondering if my transmission would work from my car or would I have to get another, because the one that is coming with the engine is an automatic and I already have a 5 speed in my 90 so is it ok if I just rebuild it and stick it back in with the 91 engine? Also i heard that I might need to get another ac compressor to use on the DE is this true?
Thanks
Little Help
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DARKSTAR21
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SunshineAcid
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i obviously didnt write this
DOHC into 90
Mechanically it all bolts up no problems.Here are the main differences:
Mechanical:Power steering - different between SOHC (pass. side) and DOHC (driver side). To swap, you need the DOHC power steering lines, reservoir, and hoses.Intake - different shape, so can't swap thatThrottle cable - SOHC too short to reach DOHC throttle body best to get a DOHC cable.A/C is a different compressor entirely, though in about the same position. To make a DOHC compressor work with a SOHC system, you'll need to have a specialty shop custom fit the DOHC lines to your SOHC system. No, the DOHC lines do not just bolt to the firewall fittings, they are different sizes. Also, SOHC systems used R12 refrigerant, now illegal. You'll need to convert to R134, which means a system flush and new drier.Ignition - I understand the '91-'94(?) sytems use a different coil, but not entirely sure. The '95+ systems don't have an external coil, so not an issue there.
Electrical - SOHC systems and DOHC systems are somewhat different in the wire routing, primarily the power/fuse wiring for the ECU (at least for the '95 vs '90 systems), but also some sensors and inputs for the OBD, tach, speedo. It's not really a big deal if 1) you have the FSM (wiring diagrams) for both the SOHC and donor DOHC systems, and 2) you can read and understand the wiring diagrams. Then its a matter of identifying the differences, and cutting/splicing the DOHC harness to match the SOHC systems. The harness plugs that connect to the engine room and dashboard harnesses are different, so you have to cut to SOHC plugs and splice them into the DOHC harness. Takes a little time and you have to do it right, but like I said, not bad if you have a bit of understanding about how electrical systems work.
Also, you need a DOHC tach as the SOHC tach will not work.
Obviously you also need the DOHC computer.
You may have to change the transmission harness a bit to make it mate up, but that's minor (for the '95, I had to wire in the 2nd O2 sensor and crankshaft position sensor, no big deal).
Mechanically it all bolts up no problems.Here are the main differences:
Mechanical:Power steering - different between SOHC (pass. side) and DOHC (driver side). To swap, you need the DOHC power steering lines, reservoir, and hoses.Intake - different shape, so can't swap thatThrottle cable - SOHC too short to reach DOHC throttle body best to get a DOHC cable.A/C is a different compressor entirely, though in about the same position. To make a DOHC compressor work with a SOHC system, you'll need to have a specialty shop custom fit the DOHC lines to your SOHC system. No, the DOHC lines do not just bolt to the firewall fittings, they are different sizes. Also, SOHC systems used R12 refrigerant, now illegal. You'll need to convert to R134, which means a system flush and new drier.Ignition - I understand the '91-'94(?) sytems use a different coil, but not entirely sure. The '95+ systems don't have an external coil, so not an issue there.
Electrical - SOHC systems and DOHC systems are somewhat different in the wire routing, primarily the power/fuse wiring for the ECU (at least for the '95 vs '90 systems), but also some sensors and inputs for the OBD, tach, speedo. It's not really a big deal if 1) you have the FSM (wiring diagrams) for both the SOHC and donor DOHC systems, and 2) you can read and understand the wiring diagrams. Then its a matter of identifying the differences, and cutting/splicing the DOHC harness to match the SOHC systems. The harness plugs that connect to the engine room and dashboard harnesses are different, so you have to cut to SOHC plugs and splice them into the DOHC harness. Takes a little time and you have to do it right, but like I said, not bad if you have a bit of understanding about how electrical systems work.
Also, you need a DOHC tach as the SOHC tach will not work.
Obviously you also need the DOHC computer.
You may have to change the transmission harness a bit to make it mate up, but that's minor (for the '95, I had to wire in the 2nd O2 sensor and crankshaft position sensor, no big deal).
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DARKSTAR21
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- Joined: Fri Apr 30, 2004 12:29 pm
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