I've read from Japanese rx7 mag. that mazda have been using the 3 piece apex seals for the 13b-rew (In Japan) , but ever since the Renesis came out they started to use the 2 piece for their rebuilt motor and that made the motor to be weaker than the ones that were built with 3 piece.
There are alot of people who blew their motor after installing the mazda reman ever since mazda made this change.

What have the mazda been using for their rebuilt motor in US? Was there any change?

 

https://www.rx7club.com/showthread.p...ece+apex+seals

this has been talked a bout before. read thru here to see what some have said or heard. I haven't had any problems yet... of course it hasn't left the shop yet. just running there and not boosting it yet. Maybe next week if my wheels get on. But the other engine i put in as well is doing OK so far

 

thanks!