camaro383

iTrader: (13)

I am tuning my friends 08 vette with a 416 stroker and vortech t-trim making approx 15psi, and dialing in the wot I had it steady at about 10.5 afr so I took out about 8% fuel and then all of a sudden the next pull its going up to 15:1 afr after a second or two into the pull, the car has tr6's gapped to 35 thousndths, I was gonna throw some tr7s in there, I haven't even pulled the plugs yet but figured I post up for some ideas

ss.slp.ls1

iTrader: (36)

What size injectors? Have you checked the duty cycle?

camaro383

iTrader: (13)

I have siemens 80lb inje@ctors which are rated at 83lbs at 3 bar fuel pressure so I set the regulator to 43.5, I have a bosch 044 pump in parllel with the stock pump and a hobbs switch for 4psi of boost, and the injector duty cycle seems to be very close btween pulls, I was thinkin that maybe the spark isn't igniting the fuel, and I know when you send raw fuel through it will read lean on the wideband

Btw I also scaled the tables 50% for the injectors

camaro383

iTrader: (13)

I put in some br7ef plugs gapped at .030 and I made about I passes and was dialing in the afr and now the same ****, so now I gotta pull the plugs again, anymore ideas lol

camaro383

iTrader: (13)

pulled the plugs, and the straps are very white, so im gonna recheck the calibration on the wideband and jump out the extra pump and see what happens, gotta make sure this hobbs switch is working

98Z28CobraKiller

iTrader: (17)

You should be running an 8 or colder. Is it still pulling when it goes lean or breaking up? .030 is also kind of a wide gap. I run the 8's at .023.

camaro383

iTrader: (13)

I thought 7's would be more than cold enough, and no when the problem happens it just pops and goes way lean, and today when it happened the car barely made it home, but the plugs weren't melted at all, just the straps were very white, like a lean condition..
I was gonna order another set of ngk 7s and run the gap at .26

ss.slp.ls1

iTrader: (36)

Are you monitoring the fuel pressure under load?

camaro383

iTrader: (13)

Only have a gauge on the regulator so no, but this is happening instantly when I hit wot at about 2k rpm where the stock pump would be able to support the power, like I said though I wanna verify this wideband is reading properly and jump the hobbs switch so I can cancel that out of the picture, and my vacuum/boost line to the regulator is kinda old and dry, so I'm gonna replace that as well, so ill let's u know where I stand tomorrow

Thanks for all the help