air 2 recycled air that is

damn.. all i have to say is DAMN! lol

well that and Doug's a genious, im not much of a switch whore.. but id love to try this out, i need to make some money and buy a kit as soon as i can lol.

seems pretty simple, use a tank larger than the volume of four bags to allow pressure to drop before returning to the compressor; at a pressure low enough to not overcome the intake reed valve in the compressor head. And when the expansion tank pressure is low enough to cause a pressure drop at the inlet, a check valve allows air to be drawn in? When the pressure in the expansion tank is higher than a set point, a simple pressure switch opens a bleed valve?

Not 100% recycle, just forced induction, set up simlilar to a turbo system (high intake manifold pressure bleeds through a blow off, low exhaust manifold pressure opens the wastegate) only the same air is being used on both sides of the turbine (compressor).

Hmmm. I may have to play with this. I'll bet there is a buttload of condensation though. The temperature changes between induction, compression, and expansion have to be enough to pull some serious water.

Edited: 8/19/2005 1:31:13 PM by maniacalmini

yeah........... i'm definately a switch whore and certainly try and incorporate this into my planned setup. one question, i will only be running a york at first and will be adding electric compressors later, prolly some 380s. will i have to have your system modified to accept the added compressors or can i just add the additional comps without any modification? i will be looking to have my truck hop consistantly for my own enjoyment, thank you

so if this works off the dump side of the bags why even take it that far. from one of your primary tanks route a line to a 5 gallon reserve for the system, makes no sense to route off dumps granted its not recyling the air but could be used the same way. just off the reserve tank use a regulator to control the psi going back to the comp. or even if you wanted use a nitrogen bottle thats regulated and feed that into the compressor. same effect. dont see why you would need to recycle the air when the compressor still at the start has to pressurize the whole system, then you can use the dump air, when you can just feed the system with another tank and accomplish the same thing. and like one guy was mentiony with this system about condinsation, does your kit include another water trap between the resevoir tank and compressor, b/c with the rapid expassion, and compression of air i'm willing to guess.. condensation might be a problem running through the compressor.

Originally posted by papaburgandy



so if this works off the dump side of the bags why even take it that far. from one of your primary tanks route a line to a 5 gallon reserve for the system, makes no sense to route off dumps granted its not recyling the air but could be used the same way. just off the reserve tank use a regulator to control the psi going back to the comp. or even if you wanted use a nitrogen bottle thats regulated and feed that into the compressor. same effect. dont see why you would need to recycle the air when the compressor still at the start has to pressurize the whole system, then you can use the dump air, when you can just feed the system with another tank and accomplish the same thing. and like one guy was mentiony with this system about condinsation, does your kit include another water trap between the resevoir tank and compressor, b/c with the rapid expassion, and compression of air i'm willing to guess.. condensation might be a problem running through the compressor.

The reserve tank needs to have a pressure greater than 1 atm to see the gains. THe reason the compressors work more efficiently with that small pressure at the inlet is they are not being required to both draw air in on the down stroke and compress it on the up stoke. Also, since there is more air in the chamber as the piston comes up (just like a turbo system), each stroke is increased in efficiency.

X volume in a smaller container has a higher pressure than the same volume in a larger container. I mean, thats essentially the definition of PSI, pounds per square inch. So by using the second tank as an expansion tank for the ~100psi bag air, the larger volume allows the pressure to drop to a low enough value that will be complimentary to the compressor. If I asked you to save 100 dollars, would it be easier or harder if I spotted you the first 15 bucks? Same thing. If the inlet air is already at 15psi (not saying thats the magic value, just picking a number) will it be easier or harder to pump to 100psi?

Of course, the longer the compressor runs, the lower and lower the reserve pressure gets, and the closer the reserve tank gets to 1 atm, the more the compressor reverts back to standard operation.

The bleeds and supply inlets I talked about were only to keep the system from being inefficient at medium pressures. Say you took enough air from your bag supply tank to turn the compressors on, the compressors would pump the tank back up using standard operation with no initial pressure in the reserve tank. (for clarity, lets call it the expansion tank from now on) There is now more air in the closed system than is needed to overdrive the compressors. If you dumped air from the bags at this point, there would be a relatively high pressure in the expansion tank, possibly higher than can be used by the compressor head without blowing by. So a bleed would open and reduce the pressure in the expansion tank to the desired value.

Conversely, if there was not sufficient air in the expansion tank to refill the compressed tank, Another bleed would open and allow outside air into the expansion tank and keep the compressor from pulling a vacuum on the dumps.

Originally posted by papaburgandy



so if this works off the dump side of the bags why even take it that far. from one of your primary tanks route a line to a 5 gallon reserve for the system, makes no sense to route off dumps granted its not recyling the air but could be used the same way. just off the reserve tank use a regulator to control the psi going back to the comp. or even if you wanted use a nitrogen bottle thats regulated and feed that into the compressor. same effect. dont see why you would need to recycle the air when the compressor still at the start has to pressurize the whole system, then you can use the dump air, when you can just feed the system with another tank and accomplish the same thing. and like one guy was mentiony with this system about condinsation, does your kit include another water trap between the resevoir tank and compressor, b/c with the rapid expassion, and compression of air i'm willing to guess.. condensation might be a problem running through the compressor.

you could just get another tank and compressor and feed the air from that tank to the main compressor...but why buy another compressor and tank...that will take up more space than a few xtra lines and fittings

it really works just like a turbo system, the wastegate lets the excess pressure out of the expansion tank, and once air in the expansion tank runs out, then the compressor draws air through a 1 way valve in the system

the thing is that DJ did all the calculations to figure out the pressure where it will operate best with your compressor...atleast give the guy some credit

Originally posted by aftershock

you could just get another tank and compressor and feed the air from that tank to the main compressor...but why buy another compressor and tank...that will take up more space than a few xtra lines and fittings.

it really works just like a turbo system, the wastegate lets the excess pressure out of the expansion tank, and once air in the expansion tank runs out, then the compressor draws air through a 1 way valve in the system

the thing is that DJ did all the calculations to figure out the pressure where it will operate best with your compressor...atleast give the guy some credit

I just watched his second video and it appears he is regulating the pressure to the compressor inlet instead of bleeding it down to have a constant volume and pressure.

I say this because:

His truck dumps less and less as he is dumping. Meaning the pressure in the expansion tank is too high to allow the dumps to dump more than to equalize the pressure between the expansion tank and the bag. Which is exacerbated by simply waiting for the compressors to make use of the expansion air and lowering the expansion pressure. You can see that happen when he holds the dumps open and the truck slowly goes down.Which would really only be a small drawback.

The way I talked about it, the air bleed would regulate the pressure (and thereby the volume) in the expansion tank with no regulator before the compressor inlet. The obvious drawback to THIS way of doing it is the bleed would eventually empty the expansion tank of any reserve, and empty the bag tank of higher pressure, meaning the second bleed would feed the compressors 0 psi inlet air and you'd be back to square one.

I dont know which way I prefer, either being up up up and wating to drop, or beiong able to dump to the ground. No doubt about it though, its easy for me to understand because he did his research, and my thoughts are just that, thoughts. Props to him for putting it to practice.

Doug your a genious... i love it man.

And I love how people are to narrow minded to comprehend the benefits of this...

I had thought of this idea a couple years ago... jsut thinking of using the dumped air in some way... never took it as far as you did... my idea never made it any further than being an idea.

i understand what your saying

yes russ, thats what i was saying...the waste gate will constantly regulate the system

buying another tank and compressor to feed into another compressor would be a big waste of space is what i'd be trying to get at...you'd be better off just using that air for the bags rather than to feed into a compressor