propellor in carb: powergains?

[vroom]

Hey guys... I was just down at our local shop and they had this neat lookin thing... It was a cylinder thing that had 2 propeller things inside it. The guy said to put it either before or after your carb and it is supposed to give massive powergains. Anyone ever heard of it? I can't find one on the computer... anyone have any info on this thing?

[310Rduner]

Don't know about for quads, but I know they make a similiar thing for cars and trucks.. goes inside the air tract after the filter, and makes the air spin around causing a venturi..

I don't see why it wouldn't work myself... it is the same principle as when you do the water spinning trick making it go down faster through the bottleneck.

[wilkin250r]

When water flows out of a bottle, it creates a vacuum within the bottle which must be replaced by air. If the water doesn't spin, and does the old "glub glub" routine, you are momentarily stopping the flow of water to allow air in. The water spinning through the bottleneck trick works because it allows water to flow down, and air to flow up inside the vortex.

If you PRESSURIZE the bottle, so that the water displacement doesn't need to be replaced by air, then you get the same flow either way.

[310Rduner]

Originally posted by wilkin250r
When water flows out of a bottle, it creates a vacuum within the bottle which must be replaced by air. If the water doesn't spin, and does the old "glub glub" routine, you are momentarily stopping the flow of water to allow air in. The water spinning through the bottleneck trick works because it allows water to flow down, and air to flow up inside the vortex.

If you PRESSURIZE the bottle, so that the water displacement doesn't need to be replaced by air, then you get the same flow either way.

:( Ok.. I was wrong

Learn something new every day:)

[JD400exrider]

Originally posted by wilkin250r
When water flows out of a bottle, it creates a vacuum within the bottle which must be replaced by air. If the water doesn't spin, and does the old "glub glub" routine, you are momentarily stopping the flow of water to allow air in. The water spinning through the bottleneck trick works because it allows water to flow down, and air to flow up inside the vortex.

If you PRESSURIZE the bottle, so that the water displacement doesn't need to be replaced by air, then you get the same flow either way.

Very nice explanation wilkin :)

This would be one of the reasons you have those plumbing vent pipes sticking out the top of the roof on your crib ;) Allows the water to drain.

[Big - D Racing]

It sounds to be just like what they make for otor vehicles and from people I talk to they tell me it actually hurts your motor rather then help it becuse that little peice actually slows down the air flow because it is disrrupting the air in the middle of its path rather than speeding it up.

[ewalker302]

I have done research on these for cars
they call them a vornado or tornado or something.

Im sure you all saw the infomercials that were running about a year ago for these things.

total scam---waste of money.

a propeller/spinner in the intake tract will not help performance at all.
unless it pressurizes the intake charge of course (super/turbo charge).

which none of these products do.

Just somebody trying to rip people off w/ bogus claims.

:bandit:

[dbsbl1]

Originally posted by JD400exrider


This would be one of the reasons you have those plumbing vent pipes sticking out the top of the roof on your crib ;) Allows the water to drain.


That and to let any sewer gas to escape instead of building up within the system.

[chucked]

i want to hook a leaf blower up to a go kart motor. hook the throttle for it up to the throttle for the motor. Ill probably have to do some mojor tuning but i bet I can get it to work.

[86atc250r]

Even if you could develop any appreciable boost with that setup you're going to run into big carburetor problems.

Think about how a carb works - vacuum from the engine draws fuel up thru the various passages to mix with the air and be drawn into the engine for combustion.

When you put boost into the carb, the higher pressure of the air coming in will force the fuel to stay in the bowl thus leaning out the engine.

If you're lucky you'll only lose some power - if you're unlucky, you'll melt some parts.

To make a "blow thru" setup work with a carb, you will have to be able to increase fuel pressure proportionally to the boost behind the carb.

-- on the other topic - no, sticking goof ball gimmicks in your intake passage will not increase performance, only reduce it. Save your money.

[secret sauc002]

i saw one of these at a k&n display at the carlisle custom compact nationals car show. it looked like it forced air into the chamber kind of like a turbo except its not running off of the exhaust. it is just magnified by the sucking power of the air filter/carb.

[wilkin250r]

Originally posted by chucked
i want to hook a leaf blower up to a go kart motor. hook the throttle for it up to the throttle for the motor. Ill probably have to do some mojor tuning but i bet I can get it to work.

Just like Gabe said, you're messing with the physics that allow a carb to work. This setup might work if you can enclose the ENTIRE carb, to equalize the air pressure, but I still bet you have problems.

Leaf blowers move large volumes of air at fairly low pressure, so you're really not going to increase cylinder pressures that much, hence little performance gain.

Just by the physics of how carburetors work, they don't work very will with forced induction.

I was always curious, why did companies make turbo kits for the 400EX and Raptor (both carbureted) and nobody made one for the Cannondale? Wouldn't the fuel injection be PERFECT for a turbo application?

[chucked]

Originally posted by wilkin250r
Just like Gabe said, you're messing with the physics that allow a carb to work. This setup might work if you can enclose the ENTIRE carb, to equalize the air pressure, but I still bet you have problems.

Leaf blowers move large volumes of air at fairly low pressure, so you're really not going to increase cylinder pressures that much, hence little performance gain.

Just by the physics of how carburetors work, they don't work very will with forced induction.

I was always curious, why did companies make turbo kits for the 400EX and Raptor (both carbureted) and nobody made one for the Cannondale? Wouldn't the fuel injection be PERFECT for a turbo application?

my leaf blower made 5 psi when it ran. 5 psi is enough for me

[86atc250r]

5psi at what flow rate?

5psi at zero flow doesn't do much good. Neither does blowing thru a carb that's not properly pressurized to equalize fuel pressure...

[ewalker302]

Originally posted by secret sauc002
i saw one of these at a k&n display at the carlisle custom compact nationals car show. it looked like it forced air into the chamber kind of like a turbo except its not running off of the exhaust. it is just magnified by the sucking power of the air filter/carb.

You are close,

The device is running off of the vacum of the carb, but nothings being magnified, it takes power to turn the blades----it robs power/velocity.


OK now you didnt hear this from me, but if you want to try a cheap boost:

Hook up a car windshield washer setup on your quad (both are 12v) put the nozzle right in front of the carb (the hole where you took out the choke will work). Then wire up a switch & fill the washer tank with straight ethanol & see what happens when you hit it wide open....................

Just be sure to put the tank & line in a cool (teperature) place.

& it may run just a tad hot so dont hold it too long.


:bandit:

[wilkin250r]

Originally posted by 86atc250r
5psi at what flow rate?

5psi at zero flow doesn't do much good. Neither does blowing thru a carb that's not properly pressurized to equalize fuel pressure...

Well, since it IS a leaf blower, I would say it probably has sufficient flow rate. High-volume, low pressure.

However, there is still the question of equalizing the fuel pressure, and pressure within the float bowl...

[86atc250r]

My point was - you can cover the end of the blower and it *may* be able to build up a small amount of pressure (5 psi would surprize me) - however, blowers/fans are not compressors - you increase the flow rate at all and any pressure it may create will go away quickly.

Either way, the leaf blower idea is a flop and is not worthy of further discussion.

[chucked]

i have an 5hp tecumseh engine on a go kart. I rigged up some vacuum hoses to the intake of the engine to the leaf blower. the engines intake valve is stuck open right now. i drilled a hold in the hose going into the intake and screwed in a guage. i turned the leaf blower on and it hit 5 psi. I will get it to work and it will work good. when i get it to work i will show u all!!! I think im going to have to get a fuel pump put in there too. now i have to get it to work good to proove a few people wrong.

[86atc250r]

So in other words you checked the pressure with zero flow --- granted a 5hp lawnmower's intake requirements will be small.... I assume you checked PSI before the carb since the stuck intake valve would have leaked any pressure.

To accurately show PSI of boost, you must measure with the engine running at WOT against a load.

You're not going to prove anyone wrong but yourself if you don't address the fuel pressure problem within the carb - and no, simply adding a fuel pump will not fix it.

Think about how a carb works.

Then research blow thru turbo setups.

Next hurdle will be if the modest internals of the lawnmower engine will survive boost for any period of time.

Good luck if you decide if your project is worth the trouble. If it were as simple as configuring a simple fan blower unit to the intake, don't you think you'd see it more often? You're certainly not the first person to think of it.

[wilkin250r]

The only way you're going to convince me is a dyno test of your mower before and after, but like Gabe says, you're still going to have to address the fuel pressure issue.

But I will disagree with Gabe on one point. If you DO succeed in solving your fuel pressure issue, and you DO see power gains, it's not going to be much, so I do think your lawnmower engine will survive...

[86atc250r]

:p

[chucked]

ill have to go to larger jettings too, i may even put a 125 carb on it.