[swinginbeef]

Is there anyone out there that has 42.5# injectors and is using an AFC2 to tune? I need my car all the time so I can't send it to be flashed with the injector change so I'm trying to use the AFC to lean them down to nearly stock levels.

I'm doing this and I'm wondering how much you are having to back off fuel. I read somewhere that if you tune the AFC to 94-95, you should be close to stock fuel. I have to tune down into the mid 80's to get my fuel trims close. Does this seem right? and what else might tuning down so drastically affect?

 

[Mr. INTENSE]

Something else must be wrong.

95% should be a good starting point for you.

 

[swinginbeef]

I recently cracked a piston and replaced with a used longblock. I never really figured out for sure exactly why I blew up the old engine, so I added 42.5# injectors and a shortstack intercooler to illiminate fuel starvation and knock as possible culprits. My fuel trims and O2's showed that I was running rich (-14.1, 950's) even before the injector swap but I wanted to be sure I never had to go through the pain of blowing up again.
What are some things I should look for that might cause all this extra fuel?