TeamRX8

iTrader: (25)

120k rotors is a fail, more than likely the apex seal slots are wallowed out. This is a Renesis issue due to the shorter apex seals (compared to previous 13B engines) putting more pressure on the slot with less depth/surface area to engage them with.

New housing and new rotors should always be on the parts list when rebuilding a Renesis with any significant mileage on it. You only got half way there. The irons should have been ground/resurfaced too.
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MincVinyl

Between our two sets of rotors, we believe the first set may have actually been newer than the 110k that was on that car. There was much less play in the apex seal slots and noticeably less wear, which was why we went with them. When that first engine was originally taken apart, as far as I can remember I had never had any compression related issues, just had a single blown coolant jacket. I admit it is rather stupid to have used rotors and new irons....then by the time I swap new rotors in, the irons will have been used.

Now we did spend a good hour or two doing a hand lapping method to resurface the irons. Essentially using a lapping compound and a large very flat granite slab made for lapping, pushing it back and forth in an infinity like pattern with some rotation. It was a great upper body work out, wasn't able to do much the rest of that day. It did succeed in cleaning up the area where the apex seal corner slides.

I live within a mile from where I work, so not many daily miles will even be put on the engine in the next few years. I plan on finding another car without rust that I can try to protect or at least get ahead of. At a certain point I know I will want to go up to the 450hp range, and likely I'll be doing a rew swap into that car fully internally built by a shop. Even if that doesn't end up happening I will want to turbo the ren by then for 350-400hp. I'd tear the motor down again and do new rotors with rx7 seals, potentially rew rotors if that turblown build flushes out more. Maybe even use part of your 4 port center iron concept to reduce heat in the Siamese sleeve and then have the 6 port side irons exhaust ported. Need to research more on that thought, but I believe those Irons should be compatible with each other. I have some other piping concepts like doing a trunk mounted radiator, deleting the mechanical water pump for a davies craig kit. Then having the IC mounted roughly where the radiator is currently. Should be able to have rather short piping compared to a grille mounted IC. As long as the rear rad is done right I will be able to avoid heat soaking the exchangers without cutting away the crash bar.

I have much to learn about turbos since I have spent most of my time dealing with the ren since highschool 7 years ago when I got my first rx8. Currently diving into learning mazdaedit and tuning basics, my brother got me an early xmas present of lessons from HPacademy which they recently did an rx7 worked example which should be interesting to get into.