how difficult is it to stick an s5 engine in an s4 body? i figured it would be covered in here somewhere but i couldn't find it. i'm hoping to get a 7 with a blown engine and swap in an s5 engine and just wondered if it mattered whether i got an s4 or s5 body. any info would be appreciated. thanks.

 

The ONLY difference between the S4 and S5 block is the front cover, you need to bolt on the front cover from your S4 block onto your S5 block, and make sure to buy the silicone O-ring to put in the front cover, under the front cover gasket. And your S4 exhaust manifold will have a MAJOR leak, you have to either use an S5 exahust manifold, or get headers. The easiest thing to do, is to use ALL the S4 wiring, sensors, intake manifold.. I mean, EVERYTHING other than what I said. Because if you try to use the S5 intake manifold or anything like that, I guarantee that if you get it started, it will be hell, because I had one that was a frankenstein like that, I will never do that again... This weekend I finished puttin an S5 block into my 86GXl.... Hopefully this should help you.. if you have any questions, e-mail me... RX7BlueVillain@yahoo.com.....

 

I was going to do the same thing except that I was going to put the s4 block into a blown s5 set up.

Then people on this forum said if you wanna do that you're going to have to drive it to the moon on a sunday at exactly 4:20 pm.

So I decided to rebuild the s5. I have a total of four Rx engines now. one completely rebuilt. One functional, but needs a rebuild while its out of the car, another completely in peices and on a shelf for quick reference and then the new s5 I just got about two weeks ago.

I just didn't want any down time on my s4 which runs fine. I'd hate to pull her out, replace the engines and have a no start.

So its just the front cover? Hmmmm. Tempting.

 

I'll backup what RX7BlueVillan said... It's very simple as long as you swap all the electronics from the S4 onto the S5.

There are only two major differences: The front covers are different and the intakes are different. You can bolt an S4 intake onto an S5 block, however, the holes for the port air won't line up. This is a whole different can of worms, so if you want more information *search* for "S5 Intake swaps"

 

thanks guys, this was really helpful. the only other thing is, what if you use the higher copmression s5 rotors in the s4 housings, and what kind of power gain is there if any? thanks again.

 

Actually, your INTAKE manifold will have a major leak, not the EXHAUST. If you bolt an S4 Manifold to an S5 motor, the middle iron has a larger hole (and yes, the gaskets are the same). What ends up happening is, you plug the hole with JB weld (which is what I did).

jarrett

 

The power gain is there, but its probably only going to net you about 15-20 ponies.

Feel free to hit me up on AIM or MSM if you have more questions. I am a veteran of this swap, and can answer any questions you may have.

Jarrett