Okay, I know that the engine in my 1990 GTU is an N/A S5 13b Man/Trans that was badly overheated and will require a total rebuild or a replacement.

I'm considering a swap from another car and have two options - but heres a few questions banging around it my head.

I am concerned about model year differences causing swapping difficulties.

1. An 88 engine with 80K miles - was the 1988 an S5 from the factory and would the swap be straight forward with the wiring harness and ECU of my 1990?



2. An 89 engine with 124K miles - Would THIS engine make a better match for the 1990 car? (for the same questions as above)

Suggestions?

Thank You
-RedRocket90

 

The 88 engine is different and is not a straight forward swap, however, what you can do is run the 88 keg (bare block) and run all S5 Accessories on it. (front cover stuff, alternator, omp...) You will want to search to see if any other specific thing needs to be done.

The 89 will be a direct swap.

For extra info, 86-88 are Series 4 (S4) cars and 89-91 are Series 5 (S5) Cars. The wiring is very different between series.

 

That's correct. I've been running an 88 block in an 89 for 4 years now. Let me find some of my old threads on it.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/fc3-s4-motor-s5-car-swap-300413/
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/omfg-s5-car-s4-engine-311548/

Noticed you are in Mo, Where at?

 

I dug this up from the thread.

 

yes, block off the egr

also you will have to grind out upper portion of s4 rear iron, so the s5 intake manifold sits properly.



the biggest problem is, the acv/egr port located directly UNDER primary ports on center iron will not line up with the corresponding port on s5 intake manifold. therefore you might have problems passing smog. make sure you seal it off good.

 

I forgot to mention that. You'll see what needs to be ground off when you fit the UIM.

Be careful of the bearing on the front cover when you take the bolt out. Give me a minute to find the info.

This also had some good info.

http://homepage.mac.com/carldavis/intake/mod.html

 

This forum is amazing - probably one of the best forums, with the most tech minded guys and gals available for any single mark. I've noticed that before - even in the mid 1990s when I owned both an 86n/a and an 88 T2, I discovered on the internet that Rx owners are tech-minded gearheads that don't mind at all diggen into the systems of what many would call a "too complicated for me" machine. And that pretty-well describes me - I'm trying to teach my Son the techniques value of staying "in tune" with your car and keepin 'em running.

Thanks again for the info...

To <inflatablepets> We're located in Blue Springs, MO and finally...

No, Mister inflatablepets, Aye am the Stig!!!

-Cheers to all