Thanks for that piece of info Karack, I never looked into the timing. I'll admit I failed there, I should've done my homework about the timing tables, I just assumed they were safe but didn't realize that Mazda aggressively tuned the timing from factory.

As for the AFR's, it seams rotaries have to run extremely rich for an optimal tune? It's a bit odd if you ask me because every other vehicle I've owned that was boosted, my AFR's were always between 11.5 and 12.5. My current other boosted car is my 2005 Civic Si, and I AFR tuned that and she stays steady at 11.9 all the way to 7000 RPMS. Is there a reason why rotaries need such super rich mixtures?

I'm not upset guys, like I said it was somewhat expected only because I had no prior knowledge as to how well (or bad) the previous owner kept up on the maintenance and storage of the engine.

Again, I'm excited for the build, 1) it'll be the first time she's been opened up, and 2) I'll be the one doing it.

I've done Honda, DSM, and Nissan builds so extra attention to detail and scrutinizing measurements and parts are well built into my work ethic. Probably helps too that I work on tens of millions of dollars worth in aircraft everday, lol.

 

Already have a plan on how it will be configured? Hybrid turbo, front mount, 3 mm Apex, etc.??? I can say that the FMIC + the Rtek 1.7 made a significant overall improvement on my '87. With recent morning temps in the low 60's (coastal S. CA) car breaks the newish 225/55 tires @ ~ 6K (just enough to reduce acceleration a bit) and continues some into 2nd. Engine: street port, 3 mm Apex, Super V + bigger T3 turbine + enlarged wastegate hybrid, ~13.5 inHg @ 950RPM, 12-13 psi boost. Haven't ran the 1/4 but sure feels a lot faster than my ex '79 L82 Vette that did 106 mph. PS - them 3mm have been good insurance for me.

 

Low afr's (under 10.5) aren't a requirement for rotary tuning, more like a bandaid for poor timing, low quality fuel, hot intake charge, improperly sized turbos and general superstition.

T onehe exception afaik is when you tune for 10's in warm weather in anticipation of cooler weather. In fl many am engine (fd's especially so it would seem) have fallen victim to a perfect 11.5 afr tune.....@ 85°. When the first cool night comes, that 11.5 becomes a 12.x -13.x pretty easily....

 

that can be tuned with air temp correction, usually they die because they're tuned to the edge of what the fuel system can manage. adding a few more psi from the colder air pushes it beyond and where the AFRs drop due to the fuel system maxing out.

 

mice