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Posted: Sat Dec 30, 2006 12:04 am
by SpudStuff
it has been tested to 280 psi...and keep in mind it is tested at optimum conditions.
All PVC pipe uses a 5:1 saftey factor. That means the pipe has a 1400 PSI burst pressure.

Posted: Sat Dec 30, 2006 1:22 am
by squeaks
I like the spark rail. What kind of voltage are you using for it? Also did you keep in mind that in a hybrid gun your maximum spark gap is inversely proportional to your mix so if you used a 4x mix you would have a 1/4 the size of gap you normally could have.

Posted: Sat Dec 30, 2006 6:53 am
by beergut
I'm not sure I understand what the spark has to do with igniting the air / fuel mixture in a hybrid? Once it's lit... it's lit. I would think any type of strong spark that would make a 1/8" crest would be sufficient to ignite the mixture...?
After all, pressure inside an internal combustion engine is much higher then in a hybrid cannon and many of these coils put out a modest 100k - 150k volts..
I work on propane engines all the time. Cylinder pressure without the explosion is at 90 - 110 psi, then add the the combustion and who knows where you're at... You can open a plug gap to 1/4" and it'll still ignite, hell, I've seen plugs with no gap igniting the mixture.

Anyway... to answer your question. I forget the formula for how many volts are needed to jump a certain size gap, I had a chart somewhere from electronics school but I cant find it. I believe it's somewhere around 75k - 100k volts because it'll jump a good 3/8" gap. I have to plug it into a 110v AC .
:D

Ya, that's my 1996 18' Stingray I/O. I just sold her though. Very nice boat, would pull 3 skiers, pop'em right out of the water. I just bought a 2000 Challenger 20' Sea-Doo jetboat... :wink: Oh sooo sweet! It has a 240hp EFI M2 Jet drive. Haven't even gotten her wet yet and I've got my hands deep into the engine. :D (why can't I just leave things alone :( )