Originally Posted by
Da55id
Thanks for the reply. What I can say is that the last tune I got prior to the crossovers, Jerry of Eurocharged who did the tune on the dyno told me there was no more fuel available in the then current setup and if I added more air Id need more fuel for sure. Are you saying that I dont need more fuel at the top end? Thanks in advance.
Ofcourse you need more fuel with the crossovers especially at high rpm this tells you your afr and you need far more than 10% more fuel.
Your ecu map gives you fuel injection time at a rpm and boost level. If your indicated boost level is lower you get lower injection time. This explains the crappy afr after installing crossovers without changing software .
(
even if your fuel system is on its limit with the right software, the afr would keep below 13 (... still to high!).)