Just for comparison, about how many pounds of N2O are you using if you have a combination like this:

500HP Nitrous Supply annular discharge fogger system:
0.40" N2O jets and 0.32" gasoline jets = @400HP tune up

Running safe rich in the quarter mile for about 6.7 seconds.

How many runs would you make on a 15 PSI bottle, leaving the line at 900PSI?

I use 10lb bottle and 2 runs works best for me - I would think 15lb you’d be good for 4 runs. As the bottle gets down it’s harder to keep pressure where you want it.

David i would bet that with that set up that you are using a little over 3 lbs per pass. Do you not weigh it before or after a run at this point? That being said i would only put 2 runs on the bottle before changing it. If not and you are logging it you will see that the expansion rate or bottle pressure falls off quicker as you get close to half of the volume. Also you should start seeing a drop off in your last split times from 1000ft to the 1320.

quote:

Originally posted by T/D6591:
David i would bet that with that set up that you are using a little over 3 lbs per pass. Do you not weigh it before or after a run at this point?

We always weight it before and after each pass.

So how much is it using David?

We had been running around 4.2-4.5 pounds a pass, started to see 5 plus all of a sudden!

Running about the same ET's. I was just looking at what others are doing.

I could get 3 passes on a 15 pound bottle, but got caught with a light bottle E1 at Vegas.

Looks like two passes now. I have 4 bottles already, and will need to buy another for safety.

quote:

Originally posted by David Gerard:
Just for comparison, about how many pounds of N2O are you using if you have a combination like this:

500HP Nitrous Supply annular discharge fogger system:
0.40" N2O jets and 0.32" gasoline jets = @400HP tune up

Running safe rich in the quarter mile for about 6.7 seconds.

How many runs would you make on a 15 PSI bottle, leaving the line at 900PSI?

I have never had an issue using 1/2 of what the bottle will hold, so two runs on a 15 pounder is pushing it with your tune up.

Also rich is not safe, in fact you can hurt it easier being rich than lean. Timing is the biggest killer out there.

We are running 34 degrees initial and use the MSD GRID to ramp down the timing by 20 degrees across 3/4 of a second, as the nitrous ramps up from 200HP to 400HP over one second.

For consistency I would use a fresh bottle each run.

New bottle each run, 950-970 psi (less drop from initial).

put a new bottle on it every pass. I use about 4 lbs. per pass using 2 kits. You'll probably be less but still need a new bottle every run.

Im not sure if others would agree but 4.5lbs a run for a .040 jet seems like a lot. Unless you are starting with the pressure high and purging down.

I was running 2 systems both with .031 nitrous jets when I ran a nitrous combination and I was only using around 3.5lbs a run.

I agree with Al on using half what the bottle will hold. When I ran 1 system I would make 2 to 3 runs on a bottle. With two systems I would change it out every run and that seemed to work ok for my combination. That was with 10lb bottle s though.

I am boxing up my manifold and nitrous system and sending them to Induction Solutions for flow testing/rebuild/etc.

Hoping to find out if we have any issues with the systems!