Hey guys...You know after watching Mad Max...and looking at his Clutched supercharger i was curious if there was such a thing? Seems like it would be possible, but have never heard of them or seem them before. Maybe i'm too young. Anyone ever experienced one?

Ed

No such animal. If the blowers not spinning, no airs getting into the motor.

Mercedes Benz makes a 469HP Supercharged V-8 with a clutch type engagement system on it.


"The impressive power of the AMG V8 comes through a belt-driven “Lysholm,” or screw-type supercharger that spins at over 23,000 rpm, making a maximum pressure of 11.6 psi, or 0.8 bar.

The supercharger is not spinning all the time. Depending on engine speed and load, the engine management computer decides whether to engage the supercharger via an electromagnetic clutch. Imperceptible to the driver, this system provides the best of both worlds – the efficiency of a non-supercharged engine at idle and part-throttle as well as the prodigious power of supercharging whenever it’s needed. "

http://www.mercedes-benz.ca/index.cfm?NewsID=178&id=611

That's news to me Dave. I guess given time any impossible task can be solved. I'd like to know how they solved the problem of getting air past the blower when its not spinning.

Back on the late 50's, early 60's there was the Lathem supercharger. The insides of it looked like a jet engine, lots of little vanes. Air and fuel flowed from front to back, or "axial" as they called it. One of the selling points listed was that if the belt broke, you could still drive the car since fuel and air could still flow through to the engine. That would have been a perfect candidate for a clutch set-up ala Mad Max.

Had a big argument with a guy in college after watching that movie. He said it was possible. I said no, if it was possible or worth it, it would have been done (this was 1987)

Andy

The "turbine" type blowers will spin and allow air to pass through them if the belt broke.

(Latham "axial-flow" type.)..............

pdq67

didn't they have a set up like that on the GTO in the movie my science project? I think it was the name. I laughed when I saw them outrunning the lighting in the power line and the kid says to turn on the blower. Jim

I believe Mercedes is also developing an electrical supercharger, once they further develop the 48V electrical system.

didn't they have a set up like that on the GTO in the movie my science project? I think it was the name. I laughed when I saw them outrunning the lighting in the power line and the kid says to turn on the blower. Jim

Funny you brought that up Jim. I was just thinking about that when I read this post. Cool movie in my opinion.

I would think that if a company were to figure out a way to vary the amount of "supercharged" air coming into the engine. Perhaps a sort of centrifigal weight setup may work.

Ive heard of people doing it but I have never seen a clutched supercharger. I know magnuson/magnacharger has a bypass valve that opens under very light throttle/steady cruise then closes as soon as you step into it. Its supposed to be a seamless transition and essentialy gives you the economy and power. They have recently released a system for gen 1 sbc and a system for gen 1 with vortec heads. I am very interested in this system and the price is very very attractive. Dale

Clutched superchargers have been around at least 20 years, Toyota employed such a setup on their "twincharged" MR2's back in the mid 80's and Koenig offered a Twincharger conversion for Ferrari Testarossa's right about the same time that used the same kind of setup (clutched roots blower for low end and turbos for top end.)

The new MB system works well, I have driven a couple examples. But as mentioned the bypass valve is critical. If you de-clutch a positive displacement supercharger without an easy way for air to go around the rotors the engine will be way down on power as it sucks through and freewheels the rotors. The more drag in the supercharger the worse it is, and if the drag is high enough it might kill the engine at low speed or idle.

With today's superchargers being quite efficient just the bypass valve is more than adequate; during cruise it takes the load off the supercharger and drops the power usage down to almost nothing. I can't think of a single "modern" (i.e. in the last 15 years) OEM supercharger setup that doesn't employ a bypass valve for light-load conditions.

i have a 1955 chevy prostreet. 396 with a 671 blower, 2 holleys (750) on top. when i built the motor i had ask the tech guy at holley, what would happen if i broke or slung a belt? should i buy a spare just in case. he told me i could still drive the car home with out a belt on it. it would not have near the power but it would drive home. so i removed the belt just to see if it would in fact even run, and to my surprise it started right up.i drove it around the yard alittle. so yes they will run without a belt.

I think I've figured out ONE way to do this IF the front of the car is long enough??

Use an old Crower crank mounted 6-71 system and install a clutch on the crank damper snout like for the tranny!! Or was it a "Moon" system???

pdq67

Hey guys...You know after watching Mad Max...and looking at his Clutched supercharger i was curious if there was such a thing?
In the movie no. The supercharger was empty and the carb was inside it. See link, midway down the page
http://www.madmaxmovies.com/cars/Replica/Black/index.html
This site has additional info on all the Mad Max movies, just about anything you would want to know, the cars, actors, triva ect...
http://www.madmaxmovies.com/

I read in one of the hot rod magazines a long time ago about someone trying to rig up an AC compressor clutch to engage/disengage blower pullies.I don't think it would be strong enough,myself.

Seen 'em run with no belt also(6-71).

For the record, you can drive a roots-blown vehicle with belt off. A friend of mine used to drive from upstate NY to E-town NJ with the belt off because he didn't want to hear the whine for four hours straight. The vacuum of the engine will keep the rotors spinning. A couple of things to keep in mind though:

-This was done with a "street" 6-71 that didn't have stripped rotors. The blower spun easily by hand because there was no contact between the rotors and the case. Had the rotors been stripped (teflon/nylatron), the vacuum would likely have not been enough to spin the blower.

-While the engine ran fine at idle and low criuse, it would run increasingly crappy as the throttle was opened because it was now way over-carbed. A car with a clutched supercharger would need to have (at least) two fuel curves, one for no boost, the other for boost.