nitrous question

[skiwesser]

With 60 shot runs great no sputter or anything, tried to go to 125 shot 42 psi fuel pressure and it came on STRONG but started sputtering at high rpm, not detonation or backfiring , but like pop,pop,pop, timing was at 11* went to 9* same thing, in fact i think it backfired through the top end (no damage), tried 90 shot same thing ??
I have a 190 lph pump, crane Hi-6 Ing. box, wet system with 1 nozzle at T.B.
Plugs looked ok def not rich, should I jack up the fuel presssure??

Help I'm supposed to go to strip on Sun.!!

 

[skiwesser]

Could my plugs be too hot?
I'm running autolite 3923's as per AFR's recommended starting point, I know nothing about heat ranges of plugs but these are long shank so autolite 24's I was running won't work.
I picked up some NGK - 8's?? dude said it was a pretty cold plug?
BTW I figure compression at 10-1, 10.25-1

 

[Marlboro_Man]

What did you set the gap on the plugs to???

 

[bubba-dough]

Yes what is the plug gap? Also just to dbl check, did you put the right fuel jet in place?

 

[RYC CUKR]

As others have said check the plug gap. I run around .035-.038 with nitrous. It sounds like the increased cylinder pressures are blowing the spark out.

 

[skiwesser]

#8 plug had gotten lose, but still ran bad at track!!
9.00 all motor
8.72 60 shot of gas 1/8mi
Pitiful for my combo I've got to find the bug in this motor!!

 

[stangjunkie]

speaking of slow combos....
RYC CUKR am i the only one that thinks your times are slow for your combo?? i've seen this a while back and often just never said anything