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MG MGB Technical - Electric Supercharging Idea?

Having seen the cheap cost of Electric superchargers compared to that of the of course far more powerful MOSS one available. I thought I might get a respectable amount of power gain by fitting an electric supercharger in front of each of my SU carburetters and wiring them so they are engaged only from 1800rpm to 5500rpm. Statistically they should add around 8-10 HP to the car, there being two of them, maybe 20? Just a quick thought that came across my mind that I thought I should ask you guys about prior to any action.


I believe there was a debate about this recently on here, and it was determined in the end that the amount of power gained would be offset by the added load on the alternator. There was also mention of the strain it would put on the alternator itself. I never read the whole thread though, so I may very well be wrong about the general consensus on this.
Anthony Morgan

Exactly how cheap are they...?

A moss s/c can (on a standard engine) put around 40-50BHP increase in power at the rear wheels, more so on a tarted up version.

So the electric s/c would need to be <500 to be cost effective.

However, if you were to undertake an experiemnt testing car before and after fitment, i would be interested in the results.

If one would give you a four or five hp increase, it doesn't necessarily follow that two would double the gain. Boost vs hp is not a linear function.
R. L Carleen

Thanks for the advice, but Phil, a MOSS supercharger via the MOSS website here in the States is $2950.00. The price of the 'lesser known brand' electric superchargers ranges from $45.00 to $90.00.


Stephen the electric SC are a joke, dont touch them a total waste of time. Autospeed tested them found them to be useless. DENIS

Stephen - you can't equate little electric fans with a real, belt driven supercharger. Moss's promotional stuff says that their device effectively doubles rear wheel horsepower. Sounds too good to be true, but the testimonies on the supercharger BBS (just click on it) bear this out. You just might get 4 - 5 hp from this fan scheme, about what you'd get by installing K&N air filters.

The old story is still true, "horsepower costs money, now, how fast do you want to go?"
John Z

Stephan, I'm the fella that started the electric super charger debate months back, and again less then a month ago. For the price your talking about is really a Marine Exhuast Inline Fan flows about 140 - 320cfm not enough to gain anything more then 1/4hp at the flywheel. I've given up on electrics and have moved on. Right now I'm looking into designing and building my own supercharger. (I can hear ya'lls groans from here...) Moss's charger is too danged bulky, and too inflexible for my tastes.
CJD Dark

This is a load of old twaddle. A mechanical supercharger probably needs say 12 kW to drive it, witnessed by the bloody great belt. At 12 V that would require 1000 amps. I think the average B alternator is rated at 60 amps. So the concept of an electric supercharger is a non starter
Paul Hollingworth

This thread was discussed between 16/03/2004 and 20/03/2004

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.