Time to rebuild?
 

Looking for some guidance: 1988 Rx7 with non-turbo, stock, 13B motor, 104,000 miles, runs great. My research tells me that I’ve been fortunate to not have issues (apex seals, eccentric shaft oil bypass valve, etc.). Should I have the engine rebuilt now or wait for something major to happen? Can’t help but feel I’m tempting fate. Your insights would be appreciated. Thanks!

If it's not smoking, starts easily when hot and otherwise "runs great", I say stop worrying and just enjoy. Driven like an adult you could have many more miles in it.
Not as familiar with the NA FC engine, but I might educate myself on what to look for in used housings. But I think most other bits....hard seals, bearings, gaskets and seals that might be needed for a rebuild should all still be available.

if it ain't broke don't fix it.

Good insights. Thanks! BTW, it does have trouble starting hot in warmer weather. Is that indicative of something going bad internally?

It wouldn't hurt to do a compression test.

^Agree. Hard(er) starting when hot is sometimes indicative of low compression. With your mileage it could be getting there. But still, if it's marginal it could last along time.

I would get it compression tested if you haven't already! If it starts easily without smoke, it should be alright for a while.

Thanks again for the replies. A compression test seems like a logical next step.

Thanks for the replies. A compression test seems like an appropriate next step.

Welcome to the forum! I would offer to perform a compression test for you free of charge if you were close enough to bring the car by at some point. Would let you know how healthy the engine is. FC engines typically last 140k miles plus. They are really good engines if they are properly maintained.