Quote: Originally Posted by rasp
Maybe someone can offer a friend of mine some assistance.
He's running AGP's DBB .50 trim with RC750 injectors, AGP's fuel return line and a Walbro 255 fuel pump. That's as far as his fueling mods go. I just installed his SAFC II on his car and it works fine. He is going to order a wideband, so we don't plan on pulling too much fuel right now until I can take note of his A/F ratio.
Here's the issue:
I have his High Throttle and Low Throttle at 5% correction across the RPM range with his LTFTs in the -3-0 range. I have his Low Throttle point set to 10% and his High Throttle point set to 60% and his fuel pressure set to 40% with vac at idle. Basically in 1st and 2nd gear his car is a monster, but when you hit 3rd, and the upper rpms, it feels like fuel is being cut and a puff of black smoke comes out of the tail pipe, signifying a rich status. In 4th gear it falls on its face at 4k rpm and the same with 5th gear, but 1st, 2nd and half of 3rd are OK. It's weird, I know.
Anyone have an idea on what I can do to remedy this until his wideband gets in?
Contrary to popular belief the 750s are way too much fuel, you'll find yourself ending up pulling 20+% out in the upper rpm range if you're on 1:1 with your returnline. Lots of timing being pulled at that rate. Lots of guys end up going static pressure and pulling a lot of fuel at idle/cruise that way they don't have to pull a ton up top where it matters. I wouldn't recommend trying that until you get you buddys wideband installed though...things can go bad in a hurry if you're not watching your afrs
