Electric Supercharger

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Simon Jones
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Electric Supercharger

Post by Simon Jones » Fri Nov 28, 2008 1:01 am

...or just a glorified hairdryer?

http://cgi.ebay.co.uk/Turbo-Supercharge ... 240%3A1318

The theory seems fine, but I'd be surprised if it made any difference on a diesel Bongo. Anyone fancy getting one to find out?
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missfixit70
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Re: Electric Supercharger

Post by missfixit70 » Fri Nov 28, 2008 1:04 am

I'd have thought it'd be a bit pointless on a turbo diesel, may be useful to dry your hair when camping :wink:
You can't polish a turd - but you can roll it in glitter.
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Re: Electric Supercharger

Post by scanner » Fri Nov 28, 2008 1:53 am

Snake oil anyone?
moonshine

Re: Electric Supercharger

Post by moonshine » Fri Nov 28, 2008 7:50 am

Bears an uncanny resemblence to a heater blower motor to me.

I doubt very much whether it would push any more air in than the existing turbo would anyway, and could possibly even restrict airflow to the engine.

Any experts out there care to comment?
Trouble at t'Mill
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Re: Electric Supercharger

Post by Trouble at t'Mill » Fri Nov 28, 2008 11:00 am

No idea if it works to any degree whatsoever, but it certainly wouldn't benefit an already-turbo'd engine.
tricky

Re: Electric Supercharger

Post by tricky » Fri Nov 28, 2008 3:23 pm

Trouble at t'Mill wrote:No idea if it works to any degree whatsoever, but it certainly wouldn't benefit an already-turbo'd engine.
Not strictly true. Superchargers and turbos have often been used together in the same application as SCs have a linear response at lower speeds, the output being directly proportional to engine speeds as they are directly coupled. Turbos windmill in the exhaust flow until the revs build and it starts to build up to increase inlet pressure. This process takes a finite time hence turbo lag. Thus in high performance applications an SC may be used to give instant response in the rev curve below peak torque output and a mechanical decoupling may be used when the TC takes over. Whether this would be wothwhile in a diesel Bongo is obviously debatable but the two boost methods are not mutually exclusive.
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Re: Electric Supercharger

Post by scanner » Fri Nov 28, 2008 4:10 pm

tricky wrote:
Trouble at t'Mill wrote:No idea if it works to any degree whatsoever, but it certainly wouldn't benefit an already-turbo'd engine.
Not strictly true. Superchargers and turbos have often been used together in the same application as SCs have a linear response at lower speeds, the output being directly proportional to engine speeds as they are directly coupled. Turbos windmill in the exhaust flow until the revs build and it starts to build up to increase inlet pressure. This process takes a finite time hence turbo lag. Thus in high performance applications an SC may be used to give instant response in the rev curve below peak torque output and a mechanical decoupling may be used when the TC takes over. Whether this would be wothwhile in a diesel Bongo is obviously debatable but the two boost methods are not mutually exclusive.
But THAT is NOT a supercharger - if anything it is an electrically powered turbocharger as it is a centrifugal blower not a linear one.

Interesting that the pictures suggest it could be useful on a Bugatti Veyron.
I wonder what percentage power increase it gives on one of those?
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Re: Electric Supercharger

Post by Trouble at t'Mill » Fri Nov 28, 2008 8:19 pm

Fair enough tricky.

I understand the differences and my comment was an 'overview'; whilst this device might make a 'noticeable' difference to a normally-aspirated engine, I don't believe for a second it would make any difference to ANY already-turbocharged vehicle.
tobongoornot

Re: Electric Supercharger

Post by tobongoornot » Sat Nov 29, 2008 4:05 pm

Taking a closer look at the ebay page it appears to require you to git an aftermarket filter which is probably a K&N which is probably where the performnace increase comes from.
shaun.m

Re: Electric Supercharger

Post by shaun.m » Sat Nov 29, 2008 5:25 pm

[-X these things are the biggest waste of space ever. Seen one fitted to a morgan plus 8, it was a faster car when the unit was removed and binned
moonshine

Re: Electric Supercharger

Post by moonshine » Sat Nov 29, 2008 7:15 pm

shaun.m wrote:[-X these things are the biggest waste of space ever. Seen one fitted to a morgan plus 8, it was a faster car when the unit was removed and binned
Seems I may have been right about it restricting airflow.
tricky

Re: Electric Supercharger

Post by tricky » Sun Nov 30, 2008 12:00 pm

scanner wrote: But THAT is NOT a supercharger - if anything it is an electrically powered turbocharger as it is a centrifugal blower not a linear one.?
If we're going to be pedantic then, no, it would not be an "electrically powered turbocharger". The full name for a turbocharger is "turbo supercharger" as it is a turbine powered supercharger driven by exhaust flow, so a turbocharger IS a supercharger. The item in the ebay ad, should it provide any advantage at all (questonable at the price), would be correctly termed an "electric supercharger" or perhaps "electrocharger. There are a number out there, generally much more expensive than that one, and there are varying reports of their effctiveness. The benefit of a turbocharger is it provides boost from "free" energy. It could be argued that the additional load that the electric unit presents to the alternator, and hence power sap on the engine, could outweigh the improvements seen.

I would predict that some ignition mapping alteration would be required to prevent pre-ignition if the charge boost was in any way signifcant. The emergence of electric superchargers is no doubt connected to the increased efficiency of alternators and electric motors and breakthroughs in material technology reducing inertia in impellers and resistance in bearings, enabling the balance of cost of input to be outweighed by the benefit of output in terms of input charge boost.
as it is a centrifugal blower not a linear one.?
You also get centrifugal superchargers and these tend to be the most efficient superchargers as they use pure rotational motion direct from the engine to compress the inlet charge....
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Re: Electric Supercharger

Post by scanner » Sun Nov 30, 2008 12:32 pm

tricky wrote:
scanner wrote: But THAT is NOT a supercharger - if anything it is an electrically powered turbocharger as it is a centrifugal blower not a linear one.?
If we're going to be pedantic then, no, it would not be an "electrically powered turbocharger". The full name for a turbocharger is "turbo supercharger" as it is a turbine powered supercharger driven by exhaust flow, so a turbocharger IS a supercharger. The item in the ebay ad, should it provide any advantage at all (questonable at the price), would be correctly termed an "electric supercharger" or perhaps "electrocharger. There are a number out there, generally much more expensive than that one, and there are varying reports of their effctiveness. The benefit of a turbocharger is it provides boost from "free" energy. It could be argued that the additional load that the electric unit presents to the alternator, and hence power sap on the engine, could outweigh the improvements seen.

I would predict that some ignition mapping alteration would be required to prevent pre-ignition if the charge boost was in any way signifcant. The emergence of electric superchargers is no doubt connected to the increased efficiency of alternators and electric motors and breakthroughs in material technology reducing inertia in impellers and resistance in bearings, enabling the balance of cost of input to be outweighed by the benefit of output in terms of input charge boost.
as it is a centrifugal blower not a linear one.?
You also get centrifugal superchargers and these tend to be the most efficient superchargers as they use pure rotational motion direct from the engine to compress the inlet charge....


To be a "supercharger" ANYTHING of any form (be as pedantic as you like there) must produce more air than the engine can consume at full throttle. i.e it must SUPERcharge the engine with air.

As Moonshine points out it is extremely doubtful if that pathetic device can do so, unless fitted to something like a 0.5cc glowplug model aeroplane engine.

QED it is not any form of supercharger - turbo, axial, positive displacement, linear or otherwise........................
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