MY CAR BACKFIRES.....PLEASE HELP

[bowtietrader]

I HAVE A LOT OF MODS, STOCK INJECTORS AND I HAVE MY FUEL PRESSURE AT 40 AND TIMING SET AT 8 DEG..I HAVE HEADS CAM INTAKE FUEL PUMP, ALL KINDS OF MORE MODS..
BUT WHEN I FLOOR MY GAS PEDAL, THE CAR BACKFIRES THEN TAKES OFF, BUT IF I EASE INTO THE PEDAL THEN IT DONT BACKFIRE AT ALL..
I PUT ALL KINDS OF MONEY INTO THIS AND STILL CANT DRIVE IT.
ANY IDEAS OR ?"S PLEASE POST..
THANKS

 

[HISSIN50]

codes? MAF clean, vac ok, etc?

good luck.

 

[NightStalkersSO]

Only 40 psi with stock injectors seems low if you have heads and stuff on the car....also...why only 8 degrees??? 10 is stock on mustangs...then bump up the fuel pressure, make sure there's no detonation

 

[blkstangman88]

i agree with the 40 psi, y is it so low, try raising it some.

 

[bowtietrader]

ok, well i was going to spray so i heard 8 was good fro spray... also i removed all my emissions stuff, so theres not much vacuum lines there.. should i try to put 30#ers in there because i have them.. also i tried to get codes and it wasnt throwing nothing.. what about my distributor???

 

[92GreenGT]

Hmm

Raise the Timming too.
Play with FP first then go from there.

 

[92GreenGT]

What h/c/i combo do you have?

 

[bowtietrader]

i have trickflow KPI heads,gt-40 upper/lower, E303 cam... 1.6 r/r
255 pump,