o ring on the rotor housing or on the irons?????? i have seen both with the parts i am collecting. is it a early late thing or is it a turbo deal. ?????

i beleive all the 12a's had the o-ring in the rotor housing.... the 13b's and 20b's have it in the irons.

i just picked up some rotor housings, they say 13b but have no o ring slot?

Can't remember which way the switch was, but all pre-'86 engines had it one way, and all '86 and later engines went the other way.

Feds is right. All engines before '86 have the coolant o-rings in the rotors housing and '86 and later have them in the iron. So, the 13B that you mentioned must be '86+. You can also tell a bit more about them by other things. The 12A and turbo 13B rotor housings have coolant passages to go into the intake, but the 13b NAs have that part blocked. Also, if the exhaust sleeve is pretty much straight through, it can be a turbo housing or early (pre-'86) housing. The '86+ NA housings have a diffuser in the exhaust sleeve (sometimes people grind them out or replace the sleeve with a turbo one for better flow).



Kent

thanks for the info!!!!!!!!!!!!!!!!!!!