about a year ago i did the lexus/550cc swap with a walbro fuel pump and never really had any problems a couple weeks ago i put on an upgraded ct 26 and just didnt feel comfortable driving it with out monitoring it so i got a wide band. to find out that it is running lean. i thought with what things i have done you werent supposed to need tuning but i could be wrong. anybody know which is the culprit to the running lean? anybody have any luck apexi safc neo?
running lean
- Thread starter boostaddict
- Start date
boostaddict;1120855 said:
I am running lean now when ever I boost. The fuel pressure fluctuates as well and the engine hesitates under load. I am not sure if it's the fuel pump going bad or the relay or other electrical issues. The fuel pump is Walbro 255.
boostaddict;1120855 said:
Do you have a fpr? The safcII should be fine for what you need. I ran my car with one for about two years making 430rwhp. I love my standalone a hundred times more though, but you can work your way up to one of those later if you need it. How lean is your car running under boost? What AFR's is it showing?
It seems to be a very common trend recently of people having fuel issues and the usual reply is, "12V fuelpump mod!" I don't buy it as people have been using walbros for YEARS without having to mess with the wiring...
what are your #s?
lets see for a reference... with my sp61, 13-14psi, at 43psi vac off, horrible power and off the scale rich. at 35 psi vac off still off the scale in boost but shredding my 245's in 2nd, so better.
something else is wrong, as i know each setup is different, but there is still a similarity between most setups that can be recognized.
lets see for a reference... with my sp61, 13-14psi, at 43psi vac off, horrible power and off the scale rich. at 35 psi vac off still off the scale in boost but shredding my 245's in 2nd, so better.
something else is wrong, as i know each setup is different, but there is still a similarity between most setups that can be recognized.
no i dont have a afpr but i did change the fuel filter when i installed the walbro but i am running my car at about 14 psi and it does break down or sputter if you will on initial boost and as my wideband reads about 13.6 at wide open throttle where as cruising it reads between 14.4 and 15.2 so i think im going to try a new fuel pump and a afpr and see what happens
Get a real Aeromotive AFPR...you will also need to drill out the "J" tube on the fuel line return. If you like your motor, do not boost with that AFR.