Will a motor from a '90 RX-7 bolt right in to an '86-'88 RX-7? Sorry if this seems dumb but I know nothing about these cars so I'm looking for some experience/knowledge. I have a chance to pick up this rex in great shape - no visible body damage or rust, clean interior, 5-spd, power roof for......$100!!!!! The motor is toast, previous owner began to tear into it and quit. He was going to have it taken to a junkyard!!! I said if they were going to get rid of it then I would take it. So for 100 beans it's mine but before I go there, I'd like to know what motors will fit the car. I'm not exactly sure what year the blown one is. Guessing around '86-'88. Thanks.

 

If you are using all of the 86-88 injection and such, then the engine block would fit with one problem, the Oil Metering Pump (OMP). In 86-88s the OMP is mechanical, and in 89-91s it is electrical. So the mechanical OMP wont work on an 89-91 engine. And the electrical one won't work with the 86-88 induction setup. An alternative to this is going with premix. This means mixing two-cycle oil into your gas tank with each fill up.

The other method is by going with the complete 89-91 engine. That means you would be using the 89-91 intake and injections systems. This requires a lot of things. To do this swap you would need:

89-91 engine complete with intake system, Air Flow Meter, all sensors and relays, complete wiring harness, 89-91 guages + trouble lights.

This would be a difficult swap to do. If you are going to do this much work, you might as well do a Turbo II swap, which would require about the same amount of work. Yet another option would be to install the 90 motor and induction, and use a haltech or some other standalone computer with it, but I believe only the haltech can work with the electric OMP.

If you want to keep it simple, just get a ported 86-88 motor, and then you might consider putting the 89-91 style upper intake on it. This would give you as much horsepower as the '90 motor would.

 

Whoa......I had no idea. Thanks for the info.

 

There are so many minor changes and differences between the two engines [I even think the motor mounts are slightly different] that it's just too much work and headache to get set up correctly. You need the correct ECU, harneness, injectors, etc... so it's a big job. It's not "drop-in" if that's what you're asking.

 

Thanks fellas for the input. These motors are so different and I have never messed with one before....lots to learn. Hmm, a guy at work here said he had an extra Corvette motor in his garage!