What is the difference between 86-88 and 89-91 housings? Can the 86-88 housings be used on a 89-91?
Thanks!

 

Yes they are interchangable. If you are swapping front housings you just have to pay attention to an oil o-ring outside of the engine on the front. Simple though. If you swap rotors then you have to interchange flywheels and counterweights.

 

Well, I have a 91 NA and it has low compression on the rear rotor. I figure if I am going to rebuild it, then I would go ahead and use new housings. Everything else would be reused rotors, ecentric shaft etc...

 

i think the spark plug locations might be a little different between the 2, would have to line them up beside each other to be sure though.
if you are concerned about emmissions, make sure that the front and rear rotor housings are in the right spot.

you could get new TII housings to get rid of the exhaust diffuser in the port.

 

Good point on the spark plug locations. I forgot about that. Since I have both style engines I need to go take a look at them and find out for sure.