oh yeah huh. that should be plenty of spark, hmm



well its either spark or fuel, you may find something when you pull it apart



i'm thinking its not fuel, unless theres something odd going on. we played with one that had a little hesitation in the midrange, wb said it was rich, but what it really was was a lean misfire, richening it up fixed it, wb reading didnt change much....



pay attention to everything when it comes apart, you may find some smoking gun

 

Based on what he's said, I suspect it's a combination of the use of the stock ECU and its weird amount of spark advance (coupled with the use of an FCD???) as well as too little octane fuel for the amount of boost (heat) the motor was taking.



B

 

I will definitly go slow in taking it all apart and inspect all sensors and harnesses. I was running a full tank of fresh sunnoco 94 bought 1 block away from the track. So i'm sure it's some of the freshest gas you can get. I think my deciding factor if I rebuild this car to prestine or drop in a jspec and sell it would be if the harness is too crispy. I'm sick of trying to fool the ECU via FCDs and subtracting percentages and adding percentages from a safc.

 

Probably the best mod you'll ever do is get rid of the stock harness. Its such a cluster-**** and I've seen soo many connectors with shorting out wires. Ditch it and go standalone.

 

why are you using a super AFC? if your adjusting your fuel with one of these be carefull as it can throw in extra timing when your leaning out your fuel, i take it your using bigger injectors? go microtech and youl never look back let us know how you go fitting the renesis shaft and other rx8 parts, i wouldnt mind doing the same in my next engine build but abit reluctant to shell out for parts i may not be able to use

 

If your "94" is the same as ours out here (ethanol blended to 94), thats probably the reason the motor grenaded... That stuff knocks in the real world sooner than pure 91 non ethanol even though its 3 points higher...That added ethanol really requires different fuel mapping on high output/fuel sensitive engines, even though they say it doesnt, you can see the difference on a wideband.... I stay away from that stuff, I just use 91 for boost up to 23 psi.



The best engine you can build, is using internals from all the same production/casting runs, its expensive, but tis the way to a motor, with bang on clearances right out of the box...Over time, mazda's machines wear, and the measurements can be a little off from castings done 12 years ago...