1984 to 1990
 

Will the motor from 1984 rx7 fit in a 1990 rx7

Bonjour .. et bienvenue au club!

This section is to find out how to enter the forum, use the board's search function, and other fun things, as well as post questions about using the site here. You would get better results if you posted your question in the New Member RX-7 Technical section.

Having said that .. the answer is yes the motor from a 1984 RX7 will fit a 1990 RX7 but very curious as to why would you want to do something like that?

Most 1984 RX7's came with a carbureted 12A engine and only produced around 100 hp. That's quite a step down from the performance of the fuel injected 13B engine that came with your 1990 RX7.

Also the engine mounts were completed different from a first generation RX7 (1979 - 1985) compared to a second generation RX7 (1986 - 1991) .. so there will be quite a bit of custom fabrication and expense involved.

As said, most 1st gen cars had the smaller 12A motor (carb'ed). In '84 & 85 you could get the fuel injected 13B but it was basic compared to the 13B that came in a '90 and made less power. Plus many little things, like the Oil Metering Pump and engine mounts, are not compatible. Basically everything you would need to source wouldn't be worth your time.
1990 engines are a lot easier to find than all the work you'll need to make an '84 work.

welcome to the board. :)

nothing that has been posted above is (technically) incorrect, but i think the simplest answer is no.

the 12A is not going to mount easily. fabrication would be required. at any rate, putting one in a Gen 2 is pretty pointless.

for the 13B, i think the S3 engines (the ones in the SE) are actually built with the provisions to mount to a Gen 2, so you could theoretically use it by swapping a few parts over, but it's not ideal (3 mm apices, heavy rotating assembly, etc.).

what happened to the engine in your '90? you're much better served by either rebuilding it if you can, or waiting until you can get a replacement - whether S5 or S4.

Thanks for all the information... the 84 to 90 swap is out!I am new to the RX7 world! i inherited the 1990 and will be looking for all the help i can get!

Thanks again for all the help!