I have a 1986.5 Supra and a guy in my town has a 1990 7MGTE for sale. I was wondering what all needed to be used to make this swap work. Do I need the square 88 motor mounts or the round ones, should i use a 88 7mgte harness and swap over certain sensors or use a 90 harness and chop the shit out of it. Has anyone done this or is it just a better idea to go with a pre 89 motor?
1990 7mgte into 86.5 body
- Thread starter MK3er
- Start date
use 87-88 gte harness and computer, its pretty much plug in play. IF you searched a little you wouldve found out that it has been done various times... there is even a sticky for it. Now let me go find it for you C:
http://www.supramania.com/forums/showthread.php?113579-Non-Turbo-to-Turbo-(NA-T)-FAQ
http://www.supramania.com/forums/showthread.php?113579-Non-Turbo-to-Turbo-(NA-T)-FAQ
There's two 2-wire coolant sensors on the waterneck you'll need to swap out as the plugs are different between 87-88 and 89-91. Either swap them or splice the plugs/pigtails into the 87-88 harness you find.
I've done pretty much the reverse, putting an '87T engine ECU and harness into my '89 body.
I didn't have to deal with the motor mounts, since mine's an early '89, and had the same mounts.
Use the mounts from your '86.5 engine. Bolt in is all good.
ECU and chassis harness plug in yellow to grey no problem. The only big issue was ABS for me, and that wasn't that big a hurdle at all. Also, there's a change in the headlight line to the ECU which may cause you an issue. I know it does the other way, but it's not a big deal. (If you don't have ABS, but the donor car did, there may be other issues to get around.)
I wouldn't try to source an older ECU and harness myself, I'd just use the ones that I have. (Though if you were closer, I'd trade you.
)
There aren't enough issues with the mismatched harness to make a big deal out of.
I didn't have to deal with the motor mounts, since mine's an early '89, and had the same mounts.
Use the mounts from your '86.5 engine. Bolt in is all good.
ECU and chassis harness plug in yellow to grey no problem. The only big issue was ABS for me, and that wasn't that big a hurdle at all. Also, there's a change in the headlight line to the ECU which may cause you an issue. I know it does the other way, but it's not a big deal. (If you don't have ABS, but the donor car did, there may be other issues to get around.)
I wouldn't try to source an older ECU and harness myself, I'd just use the ones that I have. (Though if you were closer, I'd trade you.
)There aren't enough issues with the mismatched harness to make a big deal out of.