I currently run more timing than you are, more boost than you are and have never nipped a plug in the time I've had the car running which is nearing 20 passes now. We've tuned a lot of cars that run the same fuel on more boost and timing with no issue.

We currently have a car we built and tune that is running in the 5.20's on C16 that has 250+ IAT's with 28psi of boost and it has more timing in the tune than yours. Albeit the AFR on my car and that car is richer than yours. We run -10 heat range non projected tip NGK plugs in both cars.

I would ditch the methanol injection if you're running C16. No need for it now.

What heat range plug?

 

Yeah, and what intake manifold, Martin? And with meth?

I am still running Br7EF plugs because micro does not like non-resistor plugs.

Mike

 

Single plane on mine, High-Ram on the non intercooled car. We're running straight M1 for secondary injection on the non intercooled car. No meth on mine.

I think that plug is too hot as well, but some run them with success.

 

Both much better than what I have. I may try the 8 heat range plugs again, last time I did things did not go well. Maybe just that hole for safety.

 

I hope you get it figured out!

 

I run a 10 plug

 

I feel low 12's is slightly lean with the meth injection. We just sent a set of injectors off that had 4 seasons on them and here was a 40% variance between injectors. I feel it has to do with your intake also. How much do you slow down pulling a degree or 2? Did this just start with the cooler temps or did anything else change?

 

" and here was a 40% variance between injectors"....Smartfires???