Nitrous Fail At The Track - Yep That's Me !!

[WoodBoss]

Originally Posted by Joe M 2012 2SS

Yes I got a couple passes in on Sunday. I was shocked at the results. Prior best was a 1.56 60' and 7.42 ET. After the new 1/2 shafts it cut a 1.48 60' and ran 7.27.

I figured you were busy working, you had a lot of wood to cut up last time I stopped by. Next time I'm up that way I'll drop off the good one (driver's side), maybe hide it under the grill like I did last time?


The second pass was a little slower ET @ 7.3, but the 60' was the same 1.48.
DA was 1000 on 1st pass, and I suppose a little higher on 2nd pass. How do you get 1.5 tenths from axles? I don't have a clue. But I'll take it!!!!

I did fall asleep at the light though. Worst reaction time I can recall having!

The Zex kit we both use will not send nitrous through if the amount of fuel isn't adequate. It immediately shuts nitrous off. On my first pass with it I had less than a 1/4tank of gas, the same way I ran N/A to save weight, the car didn't get enough gas through the Schrader valve and the nitrous never came on, they designed it this way so you cant run lean. I made a pass a few months later after making several passes, and had a little over a 1/4 tank, just past the 330' mark the nitrous cut off. I make sure I have at least 1/2 tank in the car now to be sure it's getting enough fuel. This is a great feature of the Zex kit that prevents you from running lean.

Sweet nice runs, those axles must have been flexing. I will have to give the people at CompCams a call regarding the ZEX PCM. I don't recall seeing a specification sheet with all the features.

[Badbubba]

Originally Posted by WoodBoss

I'll have to think about, initially I though that a fuel pressure switch may be good but Nitrous without fuel isn't flammable. Have you seen an instance where someone lost all their fuel and they had a problem? Spraying during shifting has been pretty good really, it bangs gears pretty good.

Correct, N2O is an oxidizer. But you still have fuel being applied by your injectors. So a very lean condition could occur. Yes the ZEX is to provide a fail safe, to shut the N2O off if there is not enough fuel pressure. But.......
Are you on a wot switch (tps) or button. Possibly too low of a rpm to allow the motor to ingest all the N2O and fuel. Thus the nitrous coming out of the intake/hood, the fuel pooling and then the fireball. If wanting to use N2O at a low rpm, a progressive system could help. That way your not smacking it with the full shot at a low rpm.

[WoodBoss]

Originally Posted by Badbubba

Correct, N2O is an oxidizer. But you still have fuel being applied by your injectors. So a very lean condition could occur. Yes the ZEX is to provide a fail safe, to shut the N2O off if there is not enough fuel pressure. But.......
Are you on a wot switch (tps) or button. Possibly too low of a rpm to allow the motor to ingest all the N2O and fuel. Thus the nitrous coming out of the intake/hood, the fuel pooling and then the fireball. If wanting to use N2O at a low rpm, a progressive system could help. That way your not smacking it with the full shot at a low rpm.

I'm going to go ahead with the Window switch so I can define the rpm range where the Nitrous is activated and I should not have this issue again.

[acammer]

Originally Posted by WoodBoss

I'm going to go ahead with the Window switch so I can define the rpm range where the Nitrous is activated and I should not have this issue again.

Sounds like a good choice, just a lot safer for everything.

[WoodBoss]

Originally Posted by acammer

Sounds like a good choice, just a lot safer for everything.

Thanks for the suggestion acammer, this should work well, I'll set the high limit to stay out of the rev limiter and the low limit to keep from having the issue I had again.

[acammer]

Originally Posted by WoodBoss

Thanks for the suggestion acammer, this should work well, I'll set the high limit to stay out of the rev limiter and the low limit to keep from having the issue I had again.

Perfect - just a good margin of safety. If you find the trans doesn't like the spray through the shifts you can experiment with pulling it out just before the shift point. Probably hooks fine on the track, on the street we'll do that some times to keep it hooked up on the 1-2 shift as well.