sorry need help again about nitro

[hotrod316]

new way to lose,
33% nitro, small block chevy 10.0 with 67 cc heads.
Question, we were running  ready to make a pass an the staging guy shut as off, 90 seconds later tells us to go, I close my eyes and relight the mouse. I know I should know bether! then they shut us off again, 30 seconds later lets go. I say no pull it out of the lanes. Is there a safe way to relight the motor or should  you always pull the plugs and wind mill the motor before relight the little monster.

[Supercat]

I have had this happen many time also with up to 60%. I run a mag (so with the mag grounded) I spin the engine over a few times with the fuel off. I then pull the fuel on spin the engine up and light the mag, instant light.

This happened one time so bad on off on off that we  had to top off the tank before I could make a pass

[Spud Miller]

 Spinning it over plugs out is the only safe way to do it (wedge type motor). If the cylinder has a bunch of juice in it and the piston gets to TDC (max pressure), the nitro can go off and make a big problem. I think if you shut-off with the fuel (should be pretty dry in there as a result) and restart within a minute or two (so heat soak doesn't cause the nozzles to drip into the motor) I think you'd probably be ok. But there is risk.

 I wouldn't worry about it much at 33%. I would be nervous at 60%. Begg'in for disaster at 80%. Ridiculous dangerous to restart wet above that.

 I won't shut-off at the line for a track issue unless my crew chief tells me to...AFTER he has a quick conversation with the starter. It has happened once...he ran up to the track guy who made the "shut off" signal to both myself and my competitor after we had already fired up. He told the starter that we can't restart and we're happy to idle on the low side for a minute or two if we have to. About 10 seconds later, it was determined that we were good to go and everything was fine. It would have been a big problem for no reason.

 We have started taking the stuff to the line that we'd need if we needed to quickly de-fuel the system, spin the motor dry and restart. I think we could do it in 2-3 minutes with three guys on it. The track would have no problem waiting that long for us. Since we'd start the procedure IMMEDIATELY after shutting down, they may not even end up waiting for us at all if the "issue" that caused the shut-down took a few minutes to clear up.

[hotrod316]

AGAIN THANKS FOR YOUR TIME
 STEVE MORGAN

[ricardo1967]

"... Spinning it over plugs out is the only safe way to do it (wedge type motor). ..."

Just curious, hope I'm not abusing... what would be the difference for the hemi-headed motors?

Thanks!

[George]

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