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Are you asking a serious question there or having a laugh? Sorry, but the smiley at the end has thrown me :crazy:

It would probably achieve something on a normally aspirated diesel, but it'd be totally redundant on any car that already has a proper turbocharger.
 

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Are you asking a serious question there or having a laugh? Sorry, but the smiley at the end has thrown me :crazy:

It would probably achieve something on a normally aspirated diesel, but it'd be totally redundant on any car that already has a proper turbocharger.
Its a serious question, theres a vdub with both a super and a turbo charger ...
 

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Actually, in fairness, it might help to reduce that flat spot at low RPMs before the turbo has had the chance to spin up. Beyond that, I'd say that any improvement would be very, very marginal at best. Certainly less than could be achieved by mucking about with the existing turbo's setup.
 

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Probably take more power to run it than it could produce - I notice their lovely little graph doesn't show a comparison with figures of an engine without it fitted. Considering the rate of flow normally in the intake system it would need to be mighty powerful. There's an old saying"there is no such thing as a free lunch" and "a fool is easy parted rom his money" :rofl: :rofl: :rofl: :rofl:
 

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Its a serious question, theres a vdub with both a super and a turbo charger ...
Ah, the penny's dropped. I've been mooching round their site trying to find a turbocharged VW that they've fitted one of their superchargers to.

Yep, I remember it now - fitted to the Polo and possibly the Golf. I saw a schematic of it once, and basically the supercharger was there to fill the flat spot before the turbo had spun up.

Once the turbo was providing boost, the supercharger was mechanically disengaged from the engine to prevent it from sapping the power from the engine (the main disadvantage of a proper supercharger) so even the VW design doesn't operate by running the output of one into the input of the other.

If I recall correctly, the real point of the VW twin-charged design was that it allowed them to use a particularly powerful but laggy turbo, and eliminate the lag using the supercharger. If you already have a smaller turbo, then the effect wouldn't be so dramatic. That's especially true if you have one of the later variable-geometry ones, which generate boost from much lower RPM's than fixed ones.

Superchargers tend not to be that well suited to diesels. Few manufacturers have been brave/stupid enough to try it, with Mazda being the only one I can think of off the top of my head with the 626. The car was pretty popular with taxi drivers because it offered the low-down grunt of a normally aspirated but larger diesel engine. But at higher RPM's, the supercharger not only underperforms a turbo, it saps a lot more mechanical energy out of the engine too.
 

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Discussion Starter #8
Cheers H. I didn't notice any diesel mention on the site .. Guessing the VW solution is a little more advanced!

:d
 

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The only way to effectively 'supercharge' using an electric motor is if you have something like a 10hp motor driving a turbo. So you're talking a large heavy motor with a significant battery bank (that will degrade rapidly).
 

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A big enough electric motor would generate enough energy but it would suck more energy out of the engine than it would put in.:)

Whenever I'm feeling down at times I always go to those plug-in turbo websites - have a good chuckle - cheers me up no end.:rofl::rofl:

Maybe they have discovered perpetual motion and aren't telling anyone:)
 

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A big enough electric motor would generate enough energy but it would suck more energy out of the engine than it would put in.:)
If it can work mechanically, then it can work electrically... theoretically at least. Mechanical superchargers sap power from the engine, but make up for it by adding more air and allowing enough extra fuel to be burned to more than compensate. I don't see why an electric one couldn't do the same.

What's more, an electric one can be selectively engaged only when maximum acceleration is required. If you were really clever about it, you could rig the car to disengage the alternator and run the supercharger off the battery under foot-to-the floor conditions, and then disengage the supercharger and reengage the alternator to top the battery back up during normal driving.

I'm not saying that these devices actually work, but I don't think it's fair to dismiss the theory behind them as complete rubbish.
 
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:eek:Oh no, has Max Mosley infiltrated the forum

This is begining to sound like KERS :crazy:
 

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Super chargers as they ought to be called have been around for a long time in one from or another.
The difficulty has always been getting them to be energy efficient. One of the problems affecting the electric motor drive idea is that there is a loss of energy when the electric power is being generated and then again when it is being converted back into mechanical motion.:)
 
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What's needed is the enegy created in braking, should be converted into electrical energy and used to give a HP boost.

Is this all starting to sound familiar :crazy:

Seriously tho, there are ways of doing this but they are a little way off being ready for road cars or for that matter affordable
 

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don't go for something silly like that, if its nice and cheap it means no comback when it kills your car!

if you have a diesel and actually want to notice a difference surely a re-map should be top of the list?:confused:
 

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omg I hope your all joking about "it might do something"
any one that buys/makes/uses one of these things is a joke.
Any one with the slightest technical knowledge on how engines work and how to tune an engine will know that these would NEVER do anything and more likely to act as a restriction in the air intake.

You cannot compare this to any mechanical suppercharger/turbo and it would not help a suppercharged/turboed car.
 

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I must admit as a non-mechanical/techinical person I would be very dubious of such a device. I can't see it delivering on its promises.
 

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Every system is inherently lossy whether mechanical or electrical, there's no argument in saying something is useless because it consumes more energy than it produces - I can't think of any system to date that doesn't. :confused:
 

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Every system is inherently lossy whether mechanical or electrical, there's no argument in saying something is useless because it consumes more energy than it produces - I can't think of any system to date that doesn't. :confused:

But if you can capture some of the lost energy (such as expelled exhaust gases) in a variable fashion then gains may be made or at a minimal cost:)
 
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