SpudFiles

So i built my second advanced combustion for a friend and im debugging right now and it seems like its not lighting the propane mixture??

my chamber is 188cu-in including the elbows its a short stubby chamber.. i went on burntlatke and i used the fueltool and calculated for my 7" long 1/2" sch40pvc meter according to my chamber volume at a 4.03% ratio and it said 52psi in my meter...well now i have 2 questions, is the 1/2" specification on the calculator the same as the 1/2" on my sch40 pvc pipe?? and yeah i dont understand why its not working?? its like 43 degrees here right now and i am using a bbq lighter with a spark gap thats a little longer than 1/8"

The cold weather may not let enough propane thru to build enough psi. So you may not be getting enough of a mix.

Pete Zaria posted this link on a thread of mine.

http://www.engineeringtoolbox.com/propa ... _1020.html

you might try 2 shots of 27 psi instead of 1 shot of 52 psi or try to keep your propane bottle warmer.

hmm yes but my other advance combustion works fine right now with the standard psi gived on burntklatke. its just this new one that doesnt work.

where is your sparkgap located in the chamber please post pictures so i can get a good visual. are you using a chamber fan ...specs please

FAN? dumb question on my part...

yeah well its an under over type and theres a cleanout on the other side. i have my propane injection there and my spark gap is also there. i have no fan. i cant get a fan because im out of money. and im not going to spend of my money onto this project.

Your spark working fine?

yup its a very fat spark

Fans make a huge difference especially if your not igniting. Maybe a fan could help mix the air around after charging it with propane?

ehh but with my other cannon, the chamber is 3x longer and even if i dont mix it with a fan, it still lights.

If everything is working fine, and you have no fan I would assume there may be a rich propane mix and can't ignite. Try a fan, its the only other option I can think of.

edit-Seen your previous post. But I think its either to rich or to lean.

hehe read the above^^..lol

Not very advanced w/o fan

Definitely not what I'd call an advanced combustion, basic bbq igniter and no chamber fan all you have is just a step above spray and pray. A chamber fan is 10 bucks at office depot and get a couple connectors for 9v batteries from radio shack and maybe a little switch bingo now you're on your way to an advanced combustion. i would definitely try to use a leaner mix. over fueling is the main cause of a combustion not igniting. the second would be your spark gap but since you said it is 1/8" nice and fat i would like to see a little longer i know with those piezo igniters you can get a really nice 1/4" gap as well. other than that try a fan to mix the fuel, you will definitely see an increase in power with a nice and blended fuel mix. I know with my advanced (and it is fully advanced with metered propane, chamber fan and a 12kV ignition system with dual spark gaps) I can shoot a golf ball rough guess of 1/2 mile. All i know is that when it shoots you can't see it leave the barrel or in flight, and that I have never recovered a golf ball shot for distance.

~BigGrib