Start with the smallest jsts and work your way up from there, bottle pressure is very important and need to be kept as constant as possible when your jetting .
If its pinging get out of the gas.
Different fuel pumps and different brand systems use different size jets heres how mine was recomended for jetting (cold fusion system with VW stytle fuel pump)
NOS / Fuel
17 / 17
24 / 24
36 / 36
42 / 42
With the reccomended jetting anything more than the 24 shot would be rich as hell and unless bottle pressure was sky high would surge and blubber.
And after much testing heres what works best for my setup with around 1000 psi bottle pressure
NOS / Fuel
17 / 17
28 / 24
36 / 28
42 / 36
The bigger jets affect bottle pressure bigtime, when im running the 42/36 jets I can feel bottle pressure dropping off halfway up the dune. With the 17/17 setup I can leave the bottle at room temp 600-800 psi and its damn near perfect.
Its going to take you awhile to figure out all the little kinks in the systems but that one run where it works perfect is worth it
