I bought an electric supercharger!
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From: Sydney
I think the misunderstanding is that Wisconsin is assuming that there is some major difference between the 'fan' in a leaf blower and the 'compressor' in a turbo. In my experience with leaf blowers (and it's not extensive) they generally work on the same principal as a turbo compressor. The are a spinning plate with radial fins designed to accelerate the air around a scroll by centripetal force. Not a screw propellor like a conventional fan.
One difference between a leaf blower and turbo is that generally the leaf blowers impellor is not very well designed whereas extensive R&D goes into a turbo impellor.
But the real difference is in the amount of energy required to create decent Air flow and boost. It's pretty high. Turbos work because an engine is effectively an air pump and is pushing masses of expanding gas out the exhaust and through the turbine. SCs work because they are driven directly from the crank so have a fairly decent force working for them. But as soon as you take the engines power and run it through an alternator, store it in a battery, then use it to drive an electric motor you get huge losses. Something in the order of 80%. And a car battery just can't store that much energy.
I guess it is possible to store energy over a period of time, then use it in a burst for a quick boost, but it's very wasteful and not very efficient. And even if it does work will it overcome the extra 20Kg of battery and other bits and pieces required? I doubt it.
One difference between a leaf blower and turbo is that generally the leaf blowers impellor is not very well designed whereas extensive R&D goes into a turbo impellor.
But the real difference is in the amount of energy required to create decent Air flow and boost. It's pretty high. Turbos work because an engine is effectively an air pump and is pushing masses of expanding gas out the exhaust and through the turbine. SCs work because they are driven directly from the crank so have a fairly decent force working for them. But as soon as you take the engines power and run it through an alternator, store it in a battery, then use it to drive an electric motor you get huge losses. Something in the order of 80%. And a car battery just can't store that much energy.
I guess it is possible to store energy over a period of time, then use it in a burst for a quick boost, but it's very wasteful and not very efficient. And even if it does work will it overcome the extra 20Kg of battery and other bits and pieces required? I doubt it.
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From: Metro Boston
Originally Posted by Wisconsin S2k,May 2 2005, 09:53 PM
sure... IF you can prevent the extra CFM being introduced from blowing anywhere other than into the intake manifold.
on top of that, that's assuming that it can maintain 500cfm at the ITB once there is resistance to that kind of air flow being introduced.
You know, we can go round and round with numbers and theories all day.
Bottom line is this:
A. if this actually worked, then there'd be a hell of a lot of people running around with this cheap easy to do mod.
B. if you're so certain that the theory is sound and you disagree with what i'm saying, then buy one of these ebay units, or turbonaters, etc, dyno before and after, and prove us all wrong.
on top of that, that's assuming that it can maintain 500cfm at the ITB once there is resistance to that kind of air flow being introduced.
You know, we can go round and round with numbers and theories all day.
Bottom line is this:
A. if this actually worked, then there'd be a hell of a lot of people running around with this cheap easy to do mod.
B. if you're so certain that the theory is sound and you disagree with what i'm saying, then buy one of these ebay units, or turbonaters, etc, dyno before and after, and prove us all wrong.
While the theory is sound, the implementation probably is not. The electric motor more likely than not cannot supply the rpms at an acceptable level of power usage from the alternator and/or battery.
And for their setup? That's just ridiculous unless the boost is so low that intercooling isn't needed.
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From: Milwaukee Area
Originally Posted by temin,May 3 2005, 05:04 PM
The theory IS sound. Go take some engineering classes and you might just learn something instead of spewing out "I'm right because you haven't proven me wrong."
While the theory is sound, the implementation probably is not. The electric motor more likely than not cannot supply the rpms at an acceptable level of power usage from the alternator and/or battery.
And for their setup? That's just ridiculous unless the boost is so low that intercooling isn't needed.
While the theory is sound, the implementation probably is not. The electric motor more likely than not cannot supply the rpms at an acceptable level of power usage from the alternator and/or battery.
And for their setup? That's just ridiculous unless the boost is so low that intercooling isn't needed.
I said that if you think you're going to be able to take some electric fan you buy off ebay and throw it in there it won't work. As you just admitted, some electric fan you throw into your intake won't be able to supply the power, rpms, etc, required to provide boost.
Again, if it was, we'd see lots of people with this mod, now wouldn't we...
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From: Metro Boston
Originally Posted by Wisconsin S2k,May 2 2005, 01:01 PM
this is the magic phrase right here..... BOOST.
an electric fan will provide ZERO boost no matter how hard it's spinning or how much air it's moving. the engine is still going to take in what it needs, and an electric fan is really just a hinderance to proper air flow.
a COMPRESSOR is what you need to get boost. the air is COMPRESSED in an enclosed and sealed compressor housing. you can't do that with a fan, leaf blower, or whatever else you think you can shove into your intake.
an electric fan will provide ZERO boost no matter how hard it's spinning or how much air it's moving. the engine is still going to take in what it needs, and an electric fan is really just a hinderance to proper air flow.
a COMPRESSOR is what you need to get boost. the air is COMPRESSED in an enclosed and sealed compressor housing. you can't do that with a fan, leaf blower, or whatever else you think you can shove into your intake.
You are still talking about something totally different and wrong.
You seem to think that the compressor end of the turbo isn't a fan.
WAKE UP ALREADY. IT IS A FAN. There are no subtle semantics to this. The intake impeller is a fan and it moves air by spinning. As a result of the housing in which the fan sits and the rest of the intake structure you get a container that holds this compressed air.
Want to use a "conventional" fan to do the job? Besides some design restraints that make it far from ideal such as how to not block the compressor exhaust with the drive motor, I'm sure this would work just the same.
And for putting words into your mouth? What the hell do you think you are saying here:
B. if you're so certain that the theory is sound and you disagree with what i'm saying
Again, the theory of driving a compressor with an electric motor is fine. The problem is finding the right motor and power supply for the job.
THEORY GOOD. APPLICATION BAD.
Just because you don't see it out there more doesn't mean it won't work. That is the dumbest excuse anyone can use to back up an argument. All that says is that you don't know what you are talking about.
Pneumatic valvetrains. Why don't we see these in passenger cars? They certainly work great in F1. We'd never have to worry about floating valves. You could have infinitely variable valve timing, lift, duration, you name it.
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From: Milwaukee Area
[QUOTE=temin,May 3 2005, 07:20 PM] Read what you wrote.
You are still talking about something totally different and wrong.
You seem to think that the compressor end of the turbo isn't a fan.
WAKE UP ALREADY. IT IS A FAN. There are no subtle semantics to this. The intake impeller is a fan and it moves air by spinning. As a result of the housing in which the fan sits and the rest of the intake structure you get a container that holds this compressed air.
Want to use a "conventional" fan to do the job? Besides some design restraints that make it far from ideal such as how to not block the compressor exhaust with the drive motor, I'm sure this would work just the same.
And for putting words into your mouth? What the hell do you think you are saying here:
B. if you're so certain that the theory is sound and you disagree with what i'm saying
Again, the theory of driving a compressor with an electric motor is fine. The problem is finding the right motor and power supply for the job.
THEORY GOOD. APPLICATION BAD.
You are still talking about something totally different and wrong.
You seem to think that the compressor end of the turbo isn't a fan.
WAKE UP ALREADY. IT IS A FAN. There are no subtle semantics to this. The intake impeller is a fan and it moves air by spinning. As a result of the housing in which the fan sits and the rest of the intake structure you get a container that holds this compressed air.
Want to use a "conventional" fan to do the job? Besides some design restraints that make it far from ideal such as how to not block the compressor exhaust with the drive motor, I'm sure this would work just the same.
And for putting words into your mouth? What the hell do you think you are saying here:
B. if you're so certain that the theory is sound and you disagree with what i'm saying
Again, the theory of driving a compressor with an electric motor is fine. The problem is finding the right motor and power supply for the job.
THEORY GOOD. APPLICATION BAD.
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From: Sydney
Wisconsin - I gotta say, some of your statements are pretty sweeping and general. You seem to decide on your own premises then argue them to death. It's the premises that are erroneous, not the argument.
Fact is if Wilbur and Orville had listened to all the naysayers we wouldn't be flying today. That doesn't suggest that anything you buy on ebay is good, just that a product being sold on ebay isn't necessarily bad.
A lot of poo-pooed ideas are re-thought and re-aplied and end up being useful to some extent. Like the idea of using your air conditioner to cool intake air. The air conditioner uses way more power than it can deliver in terms of cool air. It is extremely inefficient. But Ford have used it by storing an amount of air and releasing it suddenly during acceleration (very similar to this idea of storing electrical energy and releasing it in a burst). I'm not sure how advantageous this idea of Ford's is but then their whole assembly line thing in the 20's was a bit of hit so they can't all be bad.
Fact is, two people of identical beliefs can find reason to argue if they try hard enough (look at the Vatican Council for example). Doesn't mean it's worthwhile exercise however. The only true way to gain from an argument is to try and see it from the others point of view and see where the difference and merit is. You won't win many arguments that way but you'll win a lot more friends.
Fact is if Wilbur and Orville had listened to all the naysayers we wouldn't be flying today. That doesn't suggest that anything you buy on ebay is good, just that a product being sold on ebay isn't necessarily bad.
A lot of poo-pooed ideas are re-thought and re-aplied and end up being useful to some extent. Like the idea of using your air conditioner to cool intake air. The air conditioner uses way more power than it can deliver in terms of cool air. It is extremely inefficient. But Ford have used it by storing an amount of air and releasing it suddenly during acceleration (very similar to this idea of storing electrical energy and releasing it in a burst). I'm not sure how advantageous this idea of Ford's is but then their whole assembly line thing in the 20's was a bit of hit so they can't all be bad.
Fact is, two people of identical beliefs can find reason to argue if they try hard enough (look at the Vatican Council for example). Doesn't mean it's worthwhile exercise however. The only true way to gain from an argument is to try and see it from the others point of view and see where the difference and merit is. You won't win many arguments that way but you'll win a lot more friends.
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From: Metro Boston
Originally Posted by Wisconsin S2k,May 3 2005, 06:16 PM
then you continue to argue by saying "well someone who doesn't know what they're talking about says it must not work because no one does it". again.... if this ebay crap worked, people would be doing it, now wouldn't they? I don't see you lining up to buy them....
I'm beginning to see why xviper no longer partakes in conversations like this. people read what they want to see, not what you're actually saying. every reference I made to electric fan is this ebay crap such as what the user posted. you're talking about this as if some joe schmoe can take the fan out of his leaf blower and use it to make boost, which is also not true.
i dont know how much more clearly i can spell out what i was trying to say, which I even said AUS did a much better job at explaining, yet you continue to change my words around and argue with yourself.
very well then, continue to argue with yourself, because if you haven't figured out what i was referring to by now, you obviously won't any time soon.
I'm beginning to see why xviper no longer partakes in conversations like this. people read what they want to see, not what you're actually saying. every reference I made to electric fan is this ebay crap such as what the user posted. you're talking about this as if some joe schmoe can take the fan out of his leaf blower and use it to make boost, which is also not true.
i dont know how much more clearly i can spell out what i was trying to say, which I even said AUS did a much better job at explaining, yet you continue to change my words around and argue with yourself.
very well then, continue to argue with yourself, because if you haven't figured out what i was referring to by now, you obviously won't any time soon.
I'd love to see what he thinks about a turbo driven by an electric motor as opposed to an exhaust gas driven turbine.
I'd love to see his comparison between basic operation of a leaf blower and a turbo compressor.
I'd love to see what he thinks about theory vs. practical application. I'd bet he can tell the difference when someone is comparing the two.
Again you run back to the excuse "well it can't work cause nobody's got it." This particular application of the theory probably doesn't work. The fact is you are more than capable of driving a turbo compressor with an electric motor and making it boost whatever way you want.
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Originally Posted by Wisconsin S2k,May 2 2005, 01:01 PM
an electric fan will provide ZERO boost no matter how hard it's spinning or how much air it's moving. the engine is still going to take in what it needs, and an electric fan is really just a hinderance to proper air flow.
a COMPRESSOR is what you need to get boost. the air is COMPRESSED in an enclosed and sealed compressor housing. you can't do that with a fan, leaf blower, or whatever else you think you can shove into your intake.
a COMPRESSOR is what you need to get boost. the air is COMPRESSED in an enclosed and sealed compressor housing. you can't do that with a fan, leaf blower, or whatever else you think you can shove into your intake.