Thats-so-Ls

Ive got a problem i just cant figure out how to fix my problem soo im turning to you all, i have a built Ls (b18b je 8.5:1, crower rods,pnp head,crower springs n retainers) It was all runnin fine until i put the motor back in, now it seems to sputter or hesitate around 4k and 5k rpm it feels like it gets no fuel and it seems to do it the worst in 1st gear, 2nd and 3rd dont feel as bad but they do stutter a lil. (fuel system consists of a supra pump, 8an fuel lines ,SX filter and regulater, AEM fuel rail, RC 310's and vortech fmu). Now the things i did when i took the motor out is i put a new head gasket, ARP head studs and a Skunk intake manifold. I took off the skunk manifold put the stock one on and it still did it, i redid the timming to make sure it wasnt a timming thing, and no still the problem was there. Now this is what the gauges read when im driving it, when i hit 4k in first gear it stutters hesitats and the A/f gauge goes to Lean, but the fuel pressure gauge is reading pressure and if i keep it floored itll eventually pick up again. If someone knows what it is it would be soooo helpfull thank you very much. If u need any more info about anything , just go ahead and ask. thanks again

paulzy

iTrader: (1)

how's the fuel filter? Have you tested the pump yet?

Thats-so-Ls

The filter is a SX about 4 months old if anything plus the car sees about 200 miles a month if anything(weekend warrior type thing) and the pump seems to be fine i mean after it picks and the boost goes back up it hits 85 90 psi . . but i will check it just to be sure and the filter i can bypass also, ive done everything to try and figure it out and nothing (comp. test, new plugs, checked the wires, disconnected the msd, checked the valve, re-adjusted them, redid the timming belt. .injector cleaner even though it made the car run like a$$) Got a race in ROSWELL soo i need all the help i can get thanks all

TurboInteg95

How much are you boosting and what disk is in your FMU?

Evil DOHC

Your FMU is causing the problem. How much boost are you runing? If you still have the 12:1 disk, then you should change it to 6:1 or 8:1.
EVIL

Liltrix

What ECU are U using? I had the same problem when I was using the wrong head and ECU combination