I have a 99 si that i want to tune myself i have apexi neo and aem wideband. The biggest part of the question is the uego reads rich in vtec like around 11.0 to 13.0 can i lean it down reliably or is it supposed to run rich during high revs? I also have the basics i/h/e full msd.

 

I personally wouldn't lean it out more than 13:1, but the 11:1 is a tad rich. I'd target around 12.5:1 to 13:1

 

Thanks for the suggestion. It normally runs around between 14 and 15.5 before vtec without correction. Anymore suggestions would be appretiated.

 

You should post this in the Engine Management and Tuning forum.

 

an engine typically will make its best power at a ratio of around 13:1. Aim for that ratio across the board and know that you will get to a point (even before reaching peak rpm) to where the fuel graph will flatten out and you will actually have to take away fuel in order to maintain a 13:1 AFR.

 

thanks 98 i have ran lots of bolt-ons but i am new to fuel management. I have been trying to find out what ratio makes the best power.