extreme bottle pressure!
I can get 2 runs with the 150 shot off a 10 lb'er and they're both good, the 3rd I haven't tried, but I suspect it will be weak.
15 lb'ers, I think at a 200 hit I should be able to get 3 runs, the 10 lb'er's I bet the 2nd run gets weak.
I don't have a problem heating them now, as you said in the summer it's fine, but a night race (like pinks was) and in the fall it can be a problem. This Friday I have a rental day I'm going to, it's supposed to be a high of 63. That means it's gonna be about 40 when I get there, so it's a little more of a PITA. All the bottles will be in the truck for the ride up, one on the floor with the heater blowing on it on the ride there (takes about an hour and 45 min), at least one will be warm when we get there.
At what point the bottles start to run weaker I dunno, I've never really pushed it to find out.
You are absolutely right...I should have frazed that differently... I meant it's alot more challenging to heat the 15lb bottles with the normal heating elements compared to a 10lb bottles.. Aleast that is the case with my heating core.. I'm going back to the 10lb bottles for that reason alone... Or getting another heating element in addition to the one I have now....
This wrap worked wonders on the 10lb bottle but not so good with the 15lb bottle. This pic is of the my 15lb and electric heating wrap... I'm lucky if I can get it to 900psi, same heater core on a 10lb bottle 1200psi easy in 15 minutes time....
However, Too much work and danger putting a bottle near the hot rear exhaust pipes, also running hot water on the bottle prior to racing just woundn't be practical. Lastly venting your cars heater to directly hit the bottle itself, is just too much work..... Good thinking though, that's how new ideas are created...
How about mounting the bottle in the engine compartment next to the super hot headers.. Better yet cut a hole out of bottom of your driverside seat cushion and fit the bottle somehow beneathe you, put a very thin layer of cushion and cover it.. It's going to be hard seat to sit on but racing cars aren't suppose to be comfortable....Then before racing eat some taco bell bean burrito's, some broccolli and raw garlic and go to work on the bottle.... Ha Ha... Rolling down the windows for fresh air could potentially cool the bottle though.... Getting a bit silly niow, soooo sarrry...

I think I will stick to additional heating bottle wrap..






