Well yesterday we took my friends 2000 Z28 to the track for the first time with the N20. The instructions said to install the shark nozzle 2 to 6 inces from the throttle body. (NX wet kit) So we installed it approximately 3-4 inches from the throttle body. We installed a 75 shot to start out with. He purged it at the staging lights, hits it right off the line and it launches then you hear a pop and it dies. He pulls off it starts back up runs fine. Next time out we install a 50 shot and he waits a second off the line then hits it. Seems to be alright. We then bump it up to a 100 shot, he waits a second to hit it, seems to work alright. Next time out 150 shot, waits a second then hits it same thing as the first time, pops then dies for a couple seconds, then he gets it started and goes then hits it again and finishes out just fine. Now on his old LT1 Z, he hit it off the line all the time with 125 shot. A guy in a LS1 vette hits it off the line with a 150 shot. Why is it killing it off the line. One time he didn't even use it and it tried to kill it off the line. Is the shark nozzle maybe to close to the throttle body? The guy in the vette says not to move it back before the MAF with a wet kit because it will make run to rich. Any suggestions comments on what happened are appreciated.

 

It sounds almost like something my car used to do. I bet you have a really small air leak somewhere in front of the Throttle-Body.

Just my $.02,

Later,

 

Plus,

LT1's respond to N20 a lot better than LS1's.

Later,

 

Do you have a window switch on the car? If you are spraying below 3K RPM you could get a back fire in the intake. Did you check the intake for evidence of a back fire?