b16jared

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.

Marauder

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

b16jared

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

andoxviii

iTrader: (1)

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

98vtec

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.

b16jared

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.