Count me in!

 

Hkiefus.. by all means. I'd welcome the results.

Considering to make 9psi takes about 40-50HP off the crank (rough estimate based on a roots-style blower), I for one would love to see "real world" results.

 

I started thinking about this some more... instead of testing entire vehicles (which have powertrain losses), it might be more "obvious" as to what additional power (if any) a leaf-blower makes, by using an engine dyno?

This way any swing in HP in either direction would be more noticable, with less "operator" fluctuations in the testing?

 

Geeez FREDERIC, you make it sound so scientific... I was thinking something like a 1985 civic with dual leaf blowers bolted to the fenders (on the outside) with the ducts running in through the headlight holes. The local track guys would have a fit!

 

you should have said something Tuesday. i just passed a 92 Buick Somerset along to the kid next to my sister for $200. i would have wasted the money for that kind of fun. and to get together again and have some fun like that, i would even have stop taking the drugs for a day so we could get drunk and test it properly.

 

True -- but using a couple of pulleys and a belt to drive a supercharger isn't 100% efficient either.

Well, I can think of at least one reason: M-O-N-E-Y!

 

Hahahaha my friend had a good one have a electric compresser always filling a air tank in the back of his truck. Then have a hose from the air tank running into the intake and when you want a little "boost" open up the valve. Then agian he wants to put his air pump into his intake all 32 lb per hour of it. I can hear them tires just peeling off already

 

I wish, I think the KB site listed the parasitic loss for my huffer at 89HP!

 

^He's like that. And it is why we love him. He does bring up a good point. I was thinking that could reduce my 'evaluation' budget some, but I have a few friends that would 'donate' their vehicles just for the sheer stupidity of it.

I really don't need to do the tests, the physics just don't tie out. You need far more HP than is available; not to mention that what we are talking about here are really 'fans' and not 'compressors'.

 

That's it! I'm going to the salvage yard tomorrow. But i won't do it unless I can find an equally gaudy wing.

 

Since the original topic is so far astray anyway:

I actually designed one of these for a jeep 4.6 stroker. And it worked suprisingly well. I would activate the air compressor at times when I wasn't under a heavy load...cruising around town, downhill, things like that. The bottle pressure was regulated into the intake at 6 psi. The trick was getting the computer to understand there were two different ways to operate...one regular, and one boosted. When you flipped on the 6 psi boost, it blocked the intake, and gave pressure for about...maybe ten minutes b4 the tank was dry. Ours had a LOT of bugs, and was junkyard parts, so it didn't last...but your friend has the right idea. It was cool to have the boost "on demand", instead of all the time.

 

best way to have boost on demand would be to have a trigger device like on a nitrous car(one that is run off of the gas pedal, not a stupid button) and set it up so that when you are past a certain point the trigger would open a solenoid in the air line and bam, instant boost

 

I hope no one minds, I'm going to "batch reply" so I don't have to wait 60 seconds between each "post message" button click.

It's basic physics and calculations. It is science

Side note:
- I'm a natural skeptic.
- I'm a natural pessimist.
- I don't believe any HP claims whatsoever unless I see a dyno report and I know the dyno is calibrated (I find guessing at HP rather silly...)

No money to waste except gasoline for my gas powered, flow-tested leaf blower.

And maybe some hose clamps, a piece of PVC, and a huge wad of duct tape.

Sounds about right. Just so you know, I deliberately under-ballparked "50HP" to avoid several pages of "No it doesn't, yes it does" type threads. Your quoted figure is appreciated.

The way I'd want to test it is home-brew lab style. If you guys are willing to wait quite a while, I'm happy to faciliate such a test. But I don't have a running engine I'm willing to play with (since they are in vehicles), but my old crewcab's engine is coming out hopefully this spring, in which case I can regasket it and we can do several sets of 5 "rips"... before and after attachment of a gas powered blower. I have a blower and I've measured it's flow.

Most people I've had lengthy discussions with about supercharging (or turbocharging) seem to focus on achievable pressure, or achievable flow, but not both.

Having 1000cfm of flow without any pressure to maintain it results in a useless forced induction system. The reverse is true - an air compressor can easily make 100psi, but only flow 4.5cfm (for example). I've yet to see a drivable, street legal vehicle that can operate on 4.5cfm.

While both pressure and flow are important, it's the relationship of the two numbers that make for a good, or a bad, forced induction system.

Bingo. There is too much "air slippage" in a fan, whereas a compressor has minimal slippage (blowby). If you were to install a weiland 8-72 on your big-block "whatever", and don't hook up the belt, I seriously doubt you could start the engine with the blower installed. Without being rotated, it's going to act as a huge cork and restrict flow, because the clearances are so tight. On the other hand, if you install a leave blower into your intake system, and don't start the blower, the engine would still start, run and perform okay until the point where the not-running leaf blower becomes a restriction.

Oh, and boost "on demand" is easy... don't push the throttle so hard if you don't want boost

 

I like the idea of the compressed air tank with an "on demand" type release, mainly because you could have that compressed air at ambient temp.
HOWEVER (as frederic stated) you would only have a very short time with positive pressure, as to be at a sufficient flow rate you are going to have a lot of volume being released. Also, that pressure would not be able to be sustained as it releases the air.
For example a stock 460 at 2000rpms consumes around 265cfm.

Say you have a 20gallon tank that can take 4000psi (and you have something that can compress it to that before hand), it would take about 2min 40sec to empty the tank at 2000rpms, without taking into account the positive pressure (if it was creating an effective pressure of 7psi for example it would last about 1 min 50seconds).

This is assuming that all of the air entering the engine is coming from the pressure tank. I don't see any feasible way for it get air from the atmosphere AND create a positive inlet manifold pressure.

 

hate to bump a relatively old topic but...
http://videos.streetfire.net/hottest...AD23CA9564.htm
surprised me. and the NO2 part was a great idea.