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I CHANGED THE SMOG PUMP ON MY 1977 DODGE ASPEN(<SORRY)AND STARTED THINKING THAT A SMOG PUMP PUMPS AIR INTO THE EXHAUST MANIFOLDS TO MAKE SURE EVERYTHING GETS BURNED RIGHT...WOULD IT BE POSSIBLE TO USE THAT AS A VERY SMALL SUPERCHARGER USED IN A BLOW THROUGH APPLICATION...WOULD BUILD UP ENOUGH PREASSURE...THEY ARE SUPPOSED TO LAST A LONG TIME TOO! IT'D BE PRETTY INEXPENSIVE TO BUILD...MAINLY FOR STOCK MOTORS...LIKE THE JUDSON SUPERCHARGER...JUST WONDERING!

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IIINNGGUUEEEAASSUUUUU!!!!

It is not capable of producing enough pressure at the air-flow rates needed to create a significant amount of boost. If it is capable of creating some value of pressure, the accompanying airflow is not great enough to benefit an engine; likewise, if it can flow enough air, it cannot pressurize it enough to benefit the engine.
A supercharger uses a significant amount of HP to drive it. Consider a 25 to 50 HP (just a range...depending on the type of supercharger and how big will determine how much parasitic HP loss) electric motor is needed to provide the air-flow and air-pressure you need.
Try this out: hook up your shop-vac, blowing air out of the nozzle, to your stock carburetor while the engine is running. Simply compare the sounds the Shop-Vac makes as you increase the engine's RPMs. Try comparing the time from idle to some RPM value at WOT between no shop-vac and shop-vac conditions. It probably won't idle to well, but once the revs increase, there won't be much difference at all (or the shop-vac may restrict the engine, especially at higher RPMs).

I WAS JUST WONDERING...BUT DO YOU THIS AS A FACT THAT IT WON'T PRODUCE ENOUGH PRESSURE?

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IIINNGGUUEEEAASSUUUUU!!!!

Don't ask me, ask yourself that.
No, I don't know for a fact, but I'm pretty dang sure. Shop-Vac's can be found with pretty high HP electric motors (5 hp); it still could not flow enough air at a high enough pressure to supercharge your engine. Your doghouse shroud probably flows more air than that smog pump, it cannot provide enough flow and pressure to supercharge your engine. A real supercharger doesn't use up so much HP to drive it because it is terribly inefficient (well, it is, but your smog pump is no more efficient I would guess), it's becuase it takes a lot of HP to pressurize and flow that much air. The supercharger on a Top-Fuel dragster pulls something like 600HP to drive the thing at full boost.
You have to remember that to supercharge your engine, you need to provide more air flow than the engine would usually suck at the RPM...thus pressure builds up. A stock N/A engine sucks a bit less than 1600 cc's of air every two rotations (or less than 800 cc's every rotation). Multiply that volume by 800 for the amount of air the engine would suck at idle per minute (at 800 rpm). At idle, that works out to about 688 cf/m (of course this is high since the cylinder does not entirely fill due to cam timing, intake restriction, etc).
I don't think your smog pump will help the engine at idle, much less help the engine at 3000+ rpm. Sorry.

That smog pump/super charger might make a nice addition to a go-cart or mini-bike!!

688 CFM is an inaccurate calculation because you did not convert.

At 4500 RPM a 1600 could flow 126 CFM at 100% VE

22 CFM at 800 RPM.

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'59 bug-unstockStella
'88 Bronco II-unstock Sonja
"Yes, I am a smart ass."
"I'm a DUMBASS too"

But are you gutless?

You got me!
Actually I tried to convert, but instead of cubing my foot to cm conversion value, I only squared it. Hmmm...attention to detail is declining.

We all slip sometimes.

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'59 bug-unstockStella
'88 Bronco II-unstock Sonja
"Yes, I am a smart ass."
"I'm a DUMBASS too"

But are you gutless?

I was wondering about the smog pump idea too. I think it has more potential than you guys give credit for.

Here's another option. Use the smog pump to evacuate the crank case pressure.

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*** Teach a Man to Fish ***
Searoy

"I tend to lean toward a tighter gap and a
looser skirt....a little slap never hurt." -- Joe of the West

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Searoy:
<B>
Here's another option. Use the smog pump to evacuate the crank case pressure.

</B><HR></BLOCKQUOTE>

That is an old trick. Doing that allows you to run rings with less tension against the walls. Less resistance = more power. But you need to make up for the parasitc loss to be practical.

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'59 bug-unstockStella
'88 Bronco II-unstock Sonja
"Yes, I am a smart ass."
"I'm a DUMBASS too"

But are you gutless?

Go to: http://www.turborick.com/dirt.html
I'll definitely consider the smog pump when I upgrade my Beetle to a Briggs & Straton!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Sidewalk:
<B> That is an old trick. Doing that allows you to run rings with less tension against the walls. Less resistance = more power. But you need to make up for the parasitc loss to be practical.

</B><HR></BLOCKQUOTE>

Also, if you can create a true vacuum, you eliminate air-resistance. Eventhough the displacement inside the crank-case never changes throughout the crank's revolution, the pistons are still moving the air inside the case (like ported sub-boxes housing two subs firing 180 degrees out of phase...not that anyone would ever do this). Eliminating this resistance due to the pistons pushing the air back and forth should theoretically yeild improvements.
I however wonder how a true vacuum would be accomplished? Would you have to run a sand-sealed pulley? I also wonder how this vacuum may create wear on the main-seal.

Wishout a seal you would create a low pressure area still, which would be helpful. But you would draw out a lot more vapors that way. I still like the lawn mower idea. I need to remember that, I am buying a house soon...



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'59 bug-unstockStella
'88 Bronco II-unstock Sonja
"Yes, I am a smart ass."
"I'm a DUMBASS too"

But are you gutless?

from what i saw on the website...it sounds like it might work?

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IIINNGGUUEEEAASSUUUUU!!!!

You'd need one big@SS smog pump to get any real boost. I see you mentioned the Judson Supercharger, well, they are not made anymore for a reason. Heck, no one even copies the design or trys to improve on it, must be a reason.
Much better superchargers have been made since then. It was decent for the time period and would still be okay today, but why spend the bucks when a better unit can be had for the same amount of money.

http://www.vwjudsonregister.org.uk/

[This message has been edited by Mueller (edited 03-21-2002).]