mustangGT7822

1998 Mustang gt...mods while spraying were

stock tune with a 75 shot.

Plugs are AR94s from autolite.

bottle pressure was at a constant 950 psi

spray from 3000 to 5000

the car was running cut outs so basically no exhaust except the BBK shorty headers (idk if that matters because runs with and without seemed the same)

car had 93 in tank

need to know anything else???


Alright here is what happened...I can use the 75 shot and it will work fine but when i change over to the 100 shot jets the car starts popping and backfiring.

the car also wont run on the tune for the 100 shot which retards the timing so i dont think timing is my issue

am i not getting enough fuel?? not enough nitrous?? i have no idea...
Do i need to just go get a fuel pressure gauge? because i dont know what my fuel pressure is at..could my fuel pump be able to keep up with the 75 shot but the 100 is just to much?
Any help would be nice
thanks

mustangGT7822

Its a Dynotune wet kit using a NOS bottle heater...if that matters

dimebag

What are the actual jet sizes for both the 75 and the 100? Is there any tune on the car at all? Other mods?

mustangGT7822

42 / 24 is for 75
48 / 28 is for 100
57 / 32 is for the 150 that i want to try


I have an SCT chip that has four tunes on it.
a nitrous tune which i think retards the timing two degrees (i can call up american muscle if i need to and see how they tune it...i know that mail order tunes are crap but it was free)
a 91 tune
a 87 tune
and the stock tune

other mods would be in the signature but i dont really think a short throw or anything like that would affect nitrous but i have no idea it might lol.

03BottleFedGT

what are your plugs gapped at?

mustangGT7822

gapped at 0.035

mustangGT7822

"the car also wont run on the tune for the 100 shot which retards the timing so i dont think timing is my issue"

by that i mean the 75 will work but the 100 wont

dimebag

I cant see the sig on my phone...post up full mod list

mustangGT7822

sorry bout that here is the list
*BBK shorty headers
*BBK offroad x pipe
*Flowmaster 40's
*FRPP 3.73 gears
*DynoTune wet kit
*SCT 4-bank chip
*Short throw shifter
*AM Cold air

mustangGT7822

i dont understand why the 75 works but 100 wont