:help
I was wondering of someone could answer a question for me. I need to know if it is possible to swap the KA24E from my 1990 240SX SE with a KA24DE from a 91 240SX, utilizing the existing transmission. And if so what modifications (if any) will be required. I hope someone has an answer for me.
Mystic X
KA Engine Swap
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240marcuSX
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- Car: E34 525i
E46 M3
well, if youre asking if a DE will fit in the 90' the answer is yes because its the same chassis, and you'll probably have to switch the power steering lines and reservoir just like you would with the sr20 swap,i dont know about the transmission, it might???? but why do you want to do all that work with a benefit of 5 hp? for the same amount of work and a bit more money you could swap an SR in and be done with it.
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240marcuSX
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E46 M3
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sykoslider
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- Car: stuff
Last year I swapped a 95 DOHC into my 90. No, it is not entirely plug-n-play, but its close!
Mechanically it all bolts up just fine - no problems. I believe all the transmissions are interchangeable between SOHC and DOHC, but I have no experience with an auto transmission. 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. OR, you can custom-build the PS lines. I did not try this but its probably not hard for an experienced shop.Intake - different shape, so can't swap that (you're gonna go aftermarket anyway, right!?)Throttle cable - SOHC too short to reach DOHC throttle body - can route it over the top of the DOHC engine, but 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).
That's about it in a nutshell.
BTW, I did the swap because my SOHC transmission was on its way out, and I found a DOHC with 41,000 miles on it...runs perfect, like a new car!
Mechanically it all bolts up just fine - no problems. I believe all the transmissions are interchangeable between SOHC and DOHC, but I have no experience with an auto transmission. 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. OR, you can custom-build the PS lines. I did not try this but its probably not hard for an experienced shop.Intake - different shape, so can't swap that (you're gonna go aftermarket anyway, right!?)Throttle cable - SOHC too short to reach DOHC throttle body - can route it over the top of the DOHC engine, but 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).
That's about it in a nutshell.
BTW, I did the swap because my SOHC transmission was on its way out, and I found a DOHC with 41,000 miles on it...runs perfect, like a new car!
That is some good info...jmancini wrote:Last year I swapped a 95 DOHC into my 90. No, it is not entirely plug-n-play, but its close!
Mechanically it all bolts up just fine - no problems. I believe all the transmissions are interchangeable between SOHC and DOHC, but I have no experience with an auto transmission. 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. OR, you can custom-build the PS lines. I did not try this but its probably not hard for an experienced shop.Intake - different shape, so can't swap that (you're gonna go aftermarket anyway, right!?)Throttle cable - SOHC too short to reach DOHC throttle body - can route it over the top of the DOHC engine, but 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).
That's about it in a nutshell.
BTW, I did the swap because my SOHC transmission was on its way out, and I found a DOHC with 41,000 miles on it...runs perfect, like a new car!
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RefriedNismo240
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Philsnotfalling
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