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mini supercharger on bec question.
peter bland - 26/1/12 at 06:03 PM

Will the supercharger be able to handle the 12,000rpm or will it go kahhhh boooooom ?

AdrianH - 26/1/12 at 06:15 PM

I would say it would go boom, but only a guess.

But what if you gear it to have the same max rev's as on a mini.

The mini is say 1275 cc where as a bec typically what 600 to 900 cc so consider it in terms of air flow and work it out and you probably do not need to spin the supercharger as you would the engine.

Adrian

mark chandler - 26/1/12 at 06:18 PM

Depends on the pulleys, on a car it runs off the crank on a large pulley, mayde 4 x the size of the charger pulley, if the charger is designed with a max of 12,000rpm then run with a pulley ratio of 1:1, simples

iank - 26/1/12 at 06:28 PM

quote:
Originally posted by AdrianH
I would say it would go boom, but only a guess.

But what if you gear it to have the same max rev's as on a mini.

The mini is say 1275 cc where as a bec typically what 600 to 900 cc so consider it in terms of air flow and work it out and you probably do not need to spin the supercharger as you would the engine.

Adrian


The mini (BMW type) is most likely to be the donor for a supercharger. They are 1600cc.

Put the right sized pulley on and it should provide boost in the right place, Whether it's sized correctly I'll leave to the experts.

peter bland - 26/1/12 at 06:55 PM

both pulleys are about the same size so 1:1 ratio won,t be far off. Just read a post on mini forum,sombody was spinning up to 20,000rpm with out problems ,so back to the garage.

Wadders - 26/1/12 at 07:17 PM

Most of the graph's iv'e seen give the m45 a max rpm of 14,000, however the inlet temps shoot up after about 10,000rpm as does the power needed to drive the charger, (approx 20hp at 14,000 rpm) so i guess the law of diminishing returns takes effect.

You would think 1:1 would work ok in a bec provided you can keep the inlet temps down at max revs, would suspect a decent intercooler would do this. hardest bit would be modding the crank to accept the drive.

Al.

Simon - 26/1/12 at 07:30 PM

quote:
Originally posted by AdrianH

....... where as a bec typically what 600 to 900 cc

Adrian


More like at least a 1000cc (though iirc blade engine was just over 900), but R1 - 1000; ZZR1100; CBR1100; GSXR1300 etc etc

ATB

Simon

peter bland - 26/1/12 at 08:10 PM

Iv sorted the pulley on the crank,think it originaly was a Rotrex part, and looking for a intercooler and s2000 injectors. I will just have to keep the revs down to get the best out of the supercharger,well il try.

danny keenan - 27/1/12 at 08:07 AM

ho peter iv got some s2000 injectors if you are interested give me a ring.

thanks danny

Autosri - 27/1/12 at 09:47 AM

Could you not use meth injection to lower the intake temps and increase fuel octane while on boost

jeffw - 27/1/12 at 11:24 AM

You'll need to work out how much boost you will get and if the engine will stand the pressure or go booooommmm.