Hello, I'm John Williams and own a 13B powered car. I have lost compression in one rotor and need to know what year and exact engine this is for either new parts or a replacement engine. The car has some custom parts like mounts and adaptions to a Porsche torque tube so, I don't want to have to reinvent the wheel if possible. Thanks in advance for any help.

 

The intake manifold is from an '86-88 nonturbo RX-7 (Series 4 FC N/A, which is a 6 port engine) and the rest of the accessories corroborate that. The only way to know for 100% certain is to remove the intake manifold assembly and check for the way the air injection ports are shaped and the presence of an EGR valve/blanking plate or not.

I am a little cagey because while uncommon, it IS possible to do all sorts of bizarre engine creations. I have used that same intake manifold on '84-85 six port engines, and I have used it on a Turbo II based engine.

Fortunately, ANY '74-11 engine will bolt to whatever transmission setup you have, and ANY '86-91 RX-7 engine will bolt up to whatever engine mount setup you have.

 

Peejay,
Thanks for the quick reply and information.
John

 

Just to add to what Peejay said .. you could have a Series 3 13B GSL-SE engine .. or a Series 4 FC engine (which would match the intake) .. however the rotating assembly (internal rotors and e-shaft) could be different yet again.

You could have a Series 3 short block with Series 4/5 rotors .. or a Series 4 short block with RX8 Renesis rotors .. or other combinations. You would have to pull the engine apart to determine specifically which parts (apex seals, side seals etc.) are required.

 

Thanks for the help, I really appreciate it, I'm an old dog trying to learn new tricks.
John

 

Will all of my parts including the intake, fuel ejection, flywheel, exhaust, alternator, and anything else hanging on my '88 engine attach directly to this '90 engine? Thanks for any assistance in advance. John

 

I seem to recall that there may be some minor differences between an S4 block and an S5 block with regards to the intake manifold.

Do a search for S4 intake manifold on an S5 block. An S5 intake manifold on an S4 block is more common .. but a search may point you in the right direction as to what the actual differences are.

 

Thanks, I'll check that out.
John

 

I do not think the Series 4 (what you have) manifold is a direct fit on the Series 5 (what that is) engine, because there is an air injection boss under the center two intake ports that does not exist on the earlier engine. There will be a large exhaust leak unless you build up the manifold with weld or (my go-to) steel putty. Really, the Series 4 nonturbo manifold is the only 13B engine that does not have the air injection port there, and since I like those manifolds, I have a lot of experience with extending the manifold down a half inch to cover the port.

You could probably use that '90 manifold as-is but would ideally need some way of controlling it, as it does some weird variable-length trickery in ways similar to the blend doors in an HVAC unit.

 

Thanks peejay,
I'm going to look for a good Series 4. I'm going to tear mine down and try my hand and my son's hand at repairing it. We're thinking it was an apex seal but, don't how much damage it did. It would be nice to have a exact spare since the car is already tuned with Haltech management system. I have another toy that would benefit from
a rotary transplant. Thanks for the guidance.
John