hello everyone.I have a miata 1.6 NA with M45 mercedes supercharger, intercooler and speeduino ECU. the car is fine but I have problems above 6000 rpm. sometimes he stumbles and from the logs I see that he goes lean. I have a duty cycle of the injectors even at 92%, could they be small injectors? I run with stocks. I run at nearly 6 psi of compressor pressure.

I am attaching a log, so maybe someone can check if they have time ..


Thanks in advance for the advice!

 

add pre supercharger water methanol injection.
it will suck out a ton of heat and add extra fuel

 

Welcome to the forum. I will give some generic comments, and a little bit based on your provided logs.

Sounds like mis-fire. Likely spark blowout. If engine misses, then the O2 sensor will see excess O2 and will report lean.

Just before that happens (either lower RPM, or Lower pressure), what is AFR?

You may wish to post your tune as well.

I presume you are running (2) injection pulses per revolution, since 8mS is 90% duty cycle.

DNM

 

I solved the problem by mounting yellow rx8 injectors. now I have to be able to stable a good idle. I have to use a lot of fuel (11.5 AFR at idle) to have a stable idle. do you have any advice? 0.8ms injector dead time (as written on forum discussions)