I remember you...

 

O2 will start oxidizing anything combustable in it's presence like oil on the cylinder walls and oil that gets past the valve guides before it's time to start lthe combustion cycle...like pre-ignition.
N2O holds the oxygen atom until the combustion temps get around 600deg.F during the combustion cycle then the oxygen disassociates or splits from the nitrogen(s) and is available to oxidize diesel fuel. The process benefits from additional fuel since there's extra oxidizer with the N2O.

 

everyone here is thinking this wrong your imagining running pure O2 as the complete charge.
I did use it on my '69 stang to pass NJ emissions. I didn't run pure o2 into the cylinders, just enriched the % of o2 in the normal charge. I used a Burnsomatic welding set, the small propane type bottle with the o2 regulator.
It worked like a charm and that little bottle lasted about 20 minutes.
Nitrous breaks down to N2 and an O when heated so it essentially does the same thing but is exponentialy safer because at normal temps it won't support combustion.

 

I've thought about injecting compessed air into the intake manifold to help clean up the smoke during a quarter-mile or sled-pull.

What did you use, about a 10 cubic foot cylinder?

 

dunno how many cubes are in that tank. It was one of those disposables you can get a Lowes/Depot.

 

You're doing that with the turbo . . . . . . .

 

Indeed - this would make the Cummins think it has a larger turbo...

 

The problem with that is the injected air would make it harder for the turbo to add air, so you might not really gain anything.

 

If the engine requires 750 CFM at rated speed, and you injected 40 CFM at 100 psi for 15 seconds - the impeller wouldn't see much of a difference in "head pressure"

 

That's true, and you also wouldn't see much gain from that either. Inject enough to REALLY make a difference, and then see how much it affects impeller speed. I'll put it this way-if it was a great idea, don't you think it would be done routinely? I mean, nitrous works because it has more oxygen per unit mass than air, and the extreme pressure drop it undergoes (from roughly 1000 psi to whatever manifold pressure is) causes extreme cooling. Unless you propose to carry around bottled air compressed to the same pressure that nitrous is carried at, you won't see the type of cooling gain. Then, you STILL won't see the gain you get from nitrous being 30-something percent oxygen by weight. Remember also, you won't be able to carry as much mass of compressed air in the same bottle as you can nitrous. The reason is that air is not a liquid at 1000 or so psi and ordinary temperatures. Nitrous is, which means that you can get much more nitrous in a given container size at 1000 psi and normal temperatures than you can air.

 

I wonder what an average flow rate for nitrous injected into the intake manifold is?

 

It all depends on jet sizing. Some full on race cars empty 10# bottles on every pass down the 1/4mi.

 

I would get 3 full 1/4 mile passes out of a 10 pound bottle in my mustang, with a little left over. That was on a 200 hp shot, sprayed the entire 1/4 mile.

 

That makes sense - the 10# bottle in my '65 GTO is good for two full passes with the 250 HP pills in the outboard carbs.

I'm not at the shop today - anyone know how many cubic feet a 10# bottle holds?

 

It depends on what pressure it expands to when you let it out. I guess if you assume exactly 10 pounds in the bottle, you can also assume atmospheric pressure (14.7 psi if I remember right) after expansion, and there would be a formula somewhere to figure out how much it expands. I don't have such a formula though. I think I can safely say it's MANY cubic feet though.