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Guest captain doo

Supercharger?? Can this be for real

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Guest scoobtech

I don't think this can really be called a supercharger . It only pressurizes 1 psi . A supercharger is usually rated a minimum of around 6 psi & up . Looks to me from advertisement , its just some way for someone to supercharge their wallet . I doubt you would feel any change in performance . :cool:

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Guest CROSSTBOLT

Think about this like Scoobtech says: 1 psi is about 15.7psia (absolute). Since "normal" atmospheric pressure is about 30"Hg (mercury), 1psi represents 1/15 of 30" or about 32" of manifold PRESSURE. WOT shows on a MANIFOLD PRESSURE gauge ambient atmospheric pressure or about 30". 32" does NOT represent ANY significant increase. 36 to 100"Hg MP increases represent modest to WHOPPING torque increases and also require vast amounts of power to develop. 40 amps @ 12V for 2" MP is the beginning of an exponentially increasing current curve for increasing MP gains. This is why electric superchargers have not been developed. This is also why turbo- and superchargers have had great success since the 1920's.

 

Karl

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Guest lothar34

That's a bilge pump from a boat. If anything, it'll restrict the airflow and possibly break off and you'll have little plastic pieces flying into your air intake.

 

Remember the law of conservation of energy from your physical science classes? Your engine, spinning the alternator, powering that fan, is not going to make more power for the engine.

 

That's not to say it's impossible to have an electric supercharger. It would just suick more power than it makes.

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Guest Commuter

I agree... most of these things make unreasonable claims.

 

One of the "oldies" is the <a href="http://www.electricsupercharger.com" target="top">eram</a>. You can check them out.

 

There is one thing that people forget though. The principle of energy conservation is often mentioned and that much is true. There is no free lunch. But... there is a time element. The fan draws a short burst of energy (a few seconds) from the stored energy in the battery. The engine and it's electrical systems then have 'minutes' of time to replenish that after the "impulse" demand has passed. (I'm no expert on electrical systems, but this is my understanding of it.) So... there is a momentary gain to be had, even if the total overall result is less efficient.

 

These things might come into their own when electrical systems move to 36(42) Volts. Who knows.

 

Commuter

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Guest Commuter

Now this actually looks a little interesting. Just stumbled upon this when I was looking up the site address for the eram.

 

Same idea, but a centrifugal design instead of axial. And seemingly purpose made for auto application.

 

<a href="http://www.acturbo.com" target="top">ACTurbo</a>

 

???

 

Commuter

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Guest meep424

yea, the math doesn't even work. they claim it's a 1 hp motor. 40 amps x 12 volts = 480 watts. 1 hp, with zero loss, is something like 746 watts. SO... given a total electro-mechanical motor efficiency of, say, 50%, it actually outputs ~1/3hp. Like a rechargable drill...albeit a nice one.

 

in theory this idea could work. doesn't matter if it's belt-driven or electrical, except in terms of efficiency, but seems like the big 8's pulled 12 real hp or something like that to function. supposing we need 6 hp, well, do the math. that's some big wire and a really skunked batt.

 

as someone else said wisely, maybe when we get 42 volts...

 

Mike

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Guest 1 Lucky Texan

OK - some math wiz figure out how long a tank (say - a welding size tank) filled with 3Kpsi of atmospheric air would give you say 8psi boost if it could be regulated down. Sure it's gonna weigh something BUT it's PRE-compressed - only plumbing and a control valve of some type - no direct engine load or electrical load.

 

just a fun thought

 

Carl

1 Lucky Texan

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Guest Dinero

First off, there is probably little or no benefit to be derived from this "electric supercharger". BUT a properly designed electric supercharger easily could help create MORE power than it uses. The power that the electric supercharger uses is ONLY the power required to force more atomized gasoline into the cyclinder. BUT the output power comes from the potential chemical energy of the additional atomized gasoline. A supercharger is pulley driven directly off the engine, and produces more power than it uses, right?

An electric motor powerful enough to really supercharge would be huge, expensive, and inefficient. Take mechanical power from the engine, convert it into electrical power through the altenator, then convert it back into mechanical power through the "electric supercharger"-stupid.

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Guest hocrest

I started to think about flows and pressures when I had the thought of piping Oxygen into the intake and was curious as to the airflow through an engine.

 

I had the thought that a 2.2 would draw 1.1 liters of air during each revolution?

 

So at idle we would be looking at about 1100 lpm (liters per minute)?

4000 rpm sucks through 4400 lpm or 155 square feet per minute???

 

These are all NA numbers, does this sound right?? that seems like a lot of air. The passenger and cargo area of a legacy wagon is less than 135 square feet???

 

If these numbers are right, we would need 2200 lpm to provide a boost of 7 psi at 4000 rpm.

An "H" cylinder, is about 5.5 feet tall (this is the size that you usually see on a welding cart in a garage) holds about 7000 liters. That would give about 3 minutes of boost.

 

If I'm wrong let me know, but this doesn't seem to be a very practical solution.

 

...Now increasing oxygen instead of pressured air is another possibility...

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Guest 1 Lucky Texan

Well I am in no position to argue your numbers and I thank you for replying BUT you did forget that some of that 'intake' is fuel. I don't know how much - only some fraction - but still some.

 

OK - what about LOX? It is available to folks with CPD and other breathing problems I think? (yeah - we'll see a new headline after this post "GRANNY JACKED FOR OXY BY RICE BOY GRANDSON!"

 

Carl

1 Lucky Texan

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Guest hocrest

Yeah... I don't think the fuel makes up much of the total volume.

 

LOX is an alternative to delivering O2 to people with COPD. A large vessel weighs about 165 pounds and barely fits on the floor behind the passenger seat if you slide the seat all the way forward. It holds about 41 liters of Liquid Oxygen which converts to about 32,000 liters of gaseous oxygen. The problem in this aplication with using LOX is you can only get gas from the vessel as fast as the LOX boils off and converts to gas. You could get a high flow for a short time until all the gas pressure is blown out. You then need to wait for the Liquid to evaporate more gas off, creating more pressure, giving another burst of gas under pressure.

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Guest ict89saleen

Would pure Oxygen not provide instant meltdown of the combustion area?

 

Derek

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Guest 1 Lucky Texan

Oh yeah - there's that too. PLUS the incredibly hazardous concept of driving around with LOX and gasoline.

 

I thought perhaps it would be a fun exercise to think about mixing some oxygen in with the intake to boost pressure AND increase combustion. But there would be a lot more heat generated I bet.

 

There's always some downside. I once read about a BMW racing engineer talking about an engine they were running being a little over 400hp. He said they had it up to 1200hp in the 'lab' but the problem is finding the point at which it survives the race - barely.

 

Carl

1 Lucky Texan

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Guest hocrest

Yeah, what I was thinking is that Nitrous is going to give between 21% and 36% O2.

 

By adjusting the flow of oxygen from a compressed tank, I could get that percentage anywhere I want it.

 

Too much and the engine will definately turn to a lump of brittle aluminum.:(

 

Anyone have an engine nearing the end of it's life? Wanna do some experimenting?

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that thing is only as silly as a k and n filter. os if it is cheaper, then get it. it wont clean the air as good as a k and n filter though.

 

 

if you increase the ox content too much as in stoichiometric ratios you will melt pistons because the temp will go up, but not the compression ratio. you need O2 in small quantaties to slow hte burn. if you want to add something, ad nitrous.

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OMG I can't beleive that dude is still putting bilge pumps on ebay. Never buy one. I've heard horror stories of people who actually bought them. It's just some guy trying to make a quick buck and he is. It won't increase your performance. All it does is fall apart, pieces go into your engine. And boom your done for. Seriously you would get more power out of a frickin smog pump ran through a filter into your engine (beleive me I know. I did this in my younger wanting to experiment years) Never buy those "electric superchargers" either. They are worthless. It cost money to get performance. And the only way to get performance is to spend money. Or removing weight for free. If you really want to up your performance try lightening your car. For every 11lbs you remove thats close to almost a 1hp gain. Although your not really gaining horsepower it sure will feel like it. And thats a pretty cheap thing to do. For example, remove your spare, and jack. Make sure you have a cell phone and a can of fix-a-flat. Or remove all of your insulating and spray the car down with rubberized undercoating instead. Does the same exact thing only weighs less.

Sorry this post is getting long. Time for me to shut up and get back to reading other posts.

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Think about this like Scoobtech says: 1 psi is about 15.7psia (absolute). Since "normal" atmospheric pressure is about 30"Hg (mercury), 1psi represents 1/15 of 30" or about 32" of manifold PRESSURE. WOT shows on a MANIFOLD PRESSURE gauge ambient atmospheric pressure or about 30". 32" does NOT represent ANY significant increase. 36 to 100"Hg MP increases represent modest to WHOPPING torque increases and also require vast amounts of power to develop. 40 amps @ 12V for 2" MP is the beginning of an exponentially increasing current curve for increasing MP gains. This is why electric superchargers have not been developed. This is also why turbo- and superchargers have had great success since the 1920's.

 

Karl

Speaking of power to compress air, a few months ago a came across an article on Mercedes-Benz website talking about the power needed to drive the Kompressor on their sports model... can't remember which one right now.

 

Anyway, just short of redline it was drawing 45+ (think 47) HP to drive the supercharger!!! Wonder why turbochargers are popular? Can you imagine if we took 20-25HP off of the crank to supercharge our engines? Admittedly, it costs us some power directly back-pressure, but we get some back by other tuning and exhaust silencing compromises.

 

Of course, both super- and turbo- charging loses evergy efficiency but ... tough! Pedal to the metal!!!

 

On a related subject, back in the '60s people argued that intake scoops were pointless as the amount of air drag created was more than any possible power increase.

 

Moral: Don't rely too much on what people say.

 

(But, although thread "item" is no longer viewable, when I saw something like it I assumed it was an enrichening device... for the seller.)

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yes increased oxygen is called..chemical supercharging..like NOS...or methanol..3x the oxygen particals,per.....its old news...more importantly..and much cheap and life giving to your driveline is weight reduction programs...this is where the eyelids open up...

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Oh, man, does this bring back memories. About 25 years ago, me and my cousin got hold of an early '70s Dodge Dart. The thing had holes in the floor, you had to be careful where you put your feet.

 

We had this great idea to supercharge the car for cheap.

 

We put a gas powered generator in the trunk, and fit an old vacuum cleaner under the hood somehow. Plumbed the exhaust of the vacuum cleaner to the intake snorkel on the air cleaner, connected the vac to the generator, and fired her up.

 

The car ran like crap and pinged like crazy. No power at all off idle.

 

Sounds like the guy on eBay is trying to sell something similar. I don't recommend it.

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