Blowing compressed air?

[flyngtomato]

why not just mount an air compressor in ur car lmfao

[1988starter]

Originally posted by A20A1
I did that... it raised the idle 500 rpm then it died when the air ran out...

You do the crazyest things to your car so keep up the good work.

[carobotics]

Just how did you go about hooking up an air compressor?

[A20A1]

I did that... it raised the idle 500 rpm then went back down when the air ran out...

Originally posted by carobotics

Just how did you go about hooking up an air compressor?

I used a buch of hoses and valves i had from air brushing.
I ran a brass 90-degree elbow through the lid of the filter and aimed right at the primary or secondary barrel (Mind you this was at a time I knew very little about my car, let alone the keihin.) I had the on/off valve bolted to my shifter case and a long hose to the rear where the compressor was... I could have hooked up the compressor to my car so it would refill itself, but I didn't know about the AC convertors that you can buy for the car.
The tank itself wasn't too big... but the extra wieght wasn't worth the 5 seconds or so of compressed air.
Plus I doubt there was any real increase in air and fuel while the extra air was going in... though the idle raised 500 rpm if I let it all out in park.

I pulled up the the gas station filled up my small tank and used it up pretty quick.
Compressed air tanks don't hold enough air, and don't last long and the ones that do would weigh your car down like 2 peoples worth.

An air compressor might give some bump but then you'll still have intermitent use.

Here is basicly how it looked on my carb setup... since there is no real way to use the compressed air to pressurize the carb, I shot it directly into the carb secondary barrel.
I drew in where I had the hose... I removed it after I had enough of refilling the tank. You can see the duct tape where I patched up my work.

[FyreDaug]

Ok, lets say Ive got an air tank in my car that I fill up with compressed tire air from somewhere, could I rig it up to spray the compressed air down through the booster venturis of my carb (to pull more fuel through with the added air velocity) to grab a couple more horses? Ive seen something like this done to a small 4stroke motor, but never on a car.

Im currently in the process of setting up a short ram, and this idea popped up, and I need to do some fabricating to get the intake on the carb, so if this idea is logical in any way it would be easier to modify now. Anyone heard of anything?

[FyreDaug]

Andyes I realize nitrous does the same thing but in much greater volumes, im not looking for 50 or 75 horsepower from this though

[snoopyloopy]

it probably depends on how wide the stream of air is. where would the pressurized air be injected? and yeah, if it's basically the same idea as nos, then why not just inject it the same place you would inject nos?

[FyreDaug]

Well because with nitrous im only familiar with wet shots (where it sprays fuel along with the nitrous) and not so much with the dry (just spraying nitrous and using factory fuel management/delivery)

Where as with this, I would inject it down through the carb's booster venturi on the secondary, the size of the stream will be 5/8" or whatever the size of the booster venturi is... are you familiar with carbs at all? How the air gets "squished" to pull the fuel through? (bad decription, I suck at describing things)

And I'm no carb expert, thats why I drive mike crazy sometimes on here, but I know enough basic information. Maybe ill direct him to this thread...

[HondaBoy]

you do know nitrous is to make the intake air colder right? not totally increase fuel intake, unless you're fuel injected, by way of the O2 sensors and what not. so what its doing is making the oxygen intake cold as shit in turn boosting power because cold air makes more hp when burning fuel. i dont think the thing with the compressed air would do anything but make it run lean, but if you can find a way let us know. compressed air isnt cold like other gasses when compressed.

[FyreDaug]

Um no, nitrous expands into lots and lots of oxygen molecules, not just making it colder. Thats not the right terminology, but nitrous is like a turbo if you wanna think of it that way, forcing more air into the chamber, the reason for wet shots is so you dont lean out and detonate the crap outta your motor. Its purely for oxygen

[A20A1]

First off you don't want to obstruct the booster... also the air should be clean air... which usually it isn't.
Second I've said it before in other threads... the effect is so temporary.
You only get + 500 rpm at idle, thats it! There is no way to release all that air fast enough *** CFM ***, certainly not enough air to do any good at WOT.

i dont think the thing with the compressed air would do anything but make it run lean, but if you can find a way let us know. compressed air isnt cold like other gasses when compressed.

If the air expands it will lose heat... if you compress it it will heat up.
May not be as noticable as other gases perhaps?

As for running lean:
As long as air flows past the venturi it should be able to compensate for the increase in air flow past the venturi... but you also have to take into account any increase in pressure will put sligtly more resistance on the fuel coming from the fuel bowl if not compensated for. If you could generate enough pressure, meaning you're actually flowing a lot of CFM from a source to the carb, then you might lean out because you're forcing fuel back into the float bowl.
In the case of a compressed air tank I don't think you need to worry about leaning out.

At idle when I shot the compressed air through the venturi it pretty much acted as though I had blipped the thottle open and then let go. The air fuel mix was proably where it should be, not leaning out.

[lostforawhile]

this would never work,you are trying to do the same thing with an air compressor that you would do with a turbocharger. what do you think a turbo is? the cfm of air required is enormous,air compressors are designed to produce high pressure air at relativly low cfm requirments. turbo chargers are designed to produce high cfm at relativly low pressure. so your compressor does exactly the opposite of what you need it to do. in order to produce the cubic feet per minute you would need with a compressor,you would need to be towing one of those job site type compressors that run jackhammers behind your car,then the pressure would be so high your engine would probably explode just from the air pressure.

[AccordEpicenter]

why not get real useable boost guys? And nitrous is an oxidizer. At around 400 degrees it breaks down into oxygen and some other byproducts

[lostforawhile]

why not get real useable boost guys? And nitrous is an oxidizer. At around 400 degrees it breaks down into oxygen and some other byproducts

it also cools the charge, cooler charge means more can be crammed in the cyl on a particular intake stroke

[HondaBoy]

nah, i knew it burns better and all, but i thought you were meaning it would cause increased fuel output of the carb. i just kinda thumbed through when i was reading. whatever, good luck.

[FyreDaug]

I get so bored at work I come up with some wierd ideas most of the time. But you say itll only last a few seconds? Bah I was hoping for maybe 30 seconds total out of a full charge.

meh

[A20A1]

Well you want to release as much air at once as you can... you can make it last longer with a larger tank or by bleeding less air but then you're not going to get anything from it but dirty air in the carb.

[w261w261]

In 1977 I had a '74 Pantera that I fitted a nitrous setup to. In those days you lifted up the carb, and sat it down on a plate that was probably 1/2" thick. In went the nitrous, along with a big splash of fuel. The system had big warnings all over it, like "DO NOT LET THE AUXILIARY FUEL FILTER GET DIRTY!!" When that happened, when the nitrous went in without the extra fuel, it burned out the tops of the pistons.

The Pantera was a great car. The 351 Cleveland was almost bulletproof, really all you had to do from the factory was put on a Holley double-pumper, because it wouldn't corner hard on one direction. I threw out the luggage tub in the back, and fitted headers and Borla exhausts that went straight out, kind of like a muscle boat. I was afraid to blow the transaxle or clutch, so I refused burn-out starts. But on a rolling start basis, I only lost a couple of times, both to tricked-out street racing Camaros. It was fun surprising Porsche Turbos, because on paper they thought they had the Pantera. Actually, a lot of people could take a Turbo, because if you caught them with their revs down they were toast (that was the day of single big turbos, the twin turbo setup was years away. They were nothing up to about 3500rpm, because of the low compression ratio).

[89AccordResto]

Panteras are cool but they're pretty uncomfortable with that front wheel well intruding into the footwell. It's like driving while sitting diagonally.

[AccordEpicenter]

omg you had a pantera? Those are mega hot. Im surprised you didnt melt the pistons into pieces... prolly running a 75 shot or so?

[w261w261]

You did have to get used to the offset on your legs, and I'm 6'3 so it was foldup time. You didn't notice it after awhile. I was more troubled by the idea of a few wimpy pieces of Italian sheet metal between me and that big American block behind my back. I figured if I hit something hard enough I was toast. The 70's (after '72) were sucko for performance cars. In '73 the bumper standards changed (the Pantera was one of the few cars to look great afterwards, most were pretty bad), and the pollution standards got even worse. On the positive side, you could rip most of the crap off and still pass inspection. The car got very light -scary light- at speed. The first time I let it all out I was watching to see if I could touch 150, but it was just too scary...and, at that speed you're afraid to touch anything too hard. I got a new front dam and it was better.

[Versanick]

For the record, at temperatures like those which AccordEpicenter has mentioned (400degF will work. lower and higher, more at higher...), as nitrogen is N2 in its elemental form (and will readily head in that direction from any chemical reaction if it's warranted), two molecules of N2O VERY quickly dissociate into 2N2 and O2 in the presence of the heat like that of the combustion of air and fuel. The result is (obviously) a lot more useable O2 (all throughout the burn), and that's on TOP of a well placed dry shot (far away from the TB) cooling the air (and therefore, as every 11degF approximately you gain 1% power by air density, not to mention the cooler charge in itself being a good thing).

So It doesn't just (as said on MTV's True Life: I'm a Real Street Racer) "cram air into your cylinder" like was ignorantly stated by whats-his-name with the DC2 integra, but the nitrogen quickly dissociates from the oxygen to, upon ignition, (without having to compress air more) provide much more oxygen than would normally have been available in the air/fuel charge. That's where the VAST majority of the power increase comes from.

I thought of compressed air too. Actually, more specificially, the oxygen tanks you see old people running around with. It would seem that you could come up with a little piece that, over 4000rpm at WOT, you could have a fogger open up and let out some set amount of Oxygen from the big green oxygen tank, and provide a power boost. Any thoughts?

[FyreDaug]

Thats what I was kind of thinking, but it wouldnt seem that you can get enough pressure and or air from that tank for it to be doable. It would be good for 1 pass at a time and you godda refill it.