supercharging

[mac29]

Here's what could be a very dumb question, but can you
set up a supercharger so it can be turned on and off?
I am only interested in mild power boost but figure
nitros oxide would have to be replenished frequently,
and anything else I've read of would permanently alter
hp and fuel usage.

Thanks!

[beef_bourito]

paxton desings a supercharger that only turns on at wide open throttle. I think there might be more companies that do it but i haven't heard of them. are you looking for a centrifugal supercharger or positive displacement?

[curtis73]

Its possible with today's EFI and incredible amounts of tuning, but its difficult to achieve a proper state of tune during the transition.

If you want a supercharger that only turns on at WOT, you're talking about what a turbo is already designed to do. I won't get into it too much since this is a question for the forced induction forum.

I'll copy this thread over there so you get better responses.

[nissanfanatic]

If you want a supercharger that only turns on at WOT, you're talking about what a turbo is already designed to do.

Exactly. A properly sized turbo can do this with ease. You can do a setup to give power in whatever RPM range you desire. Take my car for instance: I have a .69ar turbine housing with P-trim wheel. I get spool around 4000RPM. Then you have SRT-4's that spool very quickly and make a lot of power early. Depending on how you set the turbo up, you can get power whenever and wherever you want it.

[fierojapan]

blitz uses a clutch on there "Compressor System" superchargers. they dont have systems but for a couple of cars and from what i can tell they dont give you much horse.
http://turbomagazine.com/tech/0211tur_celica03.jpg

this is blitz setup. they seem to me that they would be verry restrictive when not active. i have heard of people using AC compressor clutches on the front of a supercharger but i havent actually seen it for my self.

[RandomTask]

The Eaton M90 Supercharger on my L67 is exactly this way. There is a boost bypass solenoid the is closed under hard acceleration. Under daily driving though it remains open allowing the boost to escape into the atmosphere.

[-Jayson-]

i have an eaton M45, and it only makes boost under WOT.

[mac29]

Originally Posted by -Jayson-

i have an eaton M45, and it only makes boost under WOT.

Thank you all for the info. I had written off turbocharging but

obviously will have to give it a thorough going over.

[curtis73]

Although supercharging has obvious benefits, a turbo is incredibly variable as far as tuning is concerned. The main difference is that superchargers are belt driven and offer boost based on RPM, regardless of driving style. They provide their same potential on a sunday drive or at the track. A turbo's potential only really exists at high throttle positions. During a sunday drive, a turbo is almost non-existent. Once you open it up, that's when the turbo really provides its effort.

Both can be tuned to provide boost at different points, but a turbo seems to suit your needs quite well. You can also adjust a wastegate to provide different levels of boost rather easily, whereas a blower usually requires altering pulley ratios.