How to choose a supercharger . Clutched Supercharger?

I don't know if there is a turbo mechanism ever attempted a magnetic clutch or a mechanism to start as a centrifugal supercharger and then at sufficient exhaust flow release and become a Turbo? Sounds kinda crazy, but think of an air conditioning compressor actuation or the old fan clutch mechanism used in the 70s. Seems like something magnetic with pressure and speed monitoring and accuation would be easily accomplished with the ecus of today. Anybody seen or think that it's got a chance? I'm just crazy enough to try.

There have been several variations of the theme, using sequential and parallel designs, some with bypasses but, AFAIK, no clutched drive to the supercharger because of the torque capacity required. The Mad Max setup was a fake.

There are (or were up to recently) some manufacturers offering such systems in production vehicles, such as VW. Gale Banks has done quite a lot of research and testing on this for diesel engines - it's very interesting and he goes into it in some detail - pressure ratios, temperature gradients, mass density, pumping losses, etc. I STRONGLY recommend his channel - https://www.youtube.com/channel/UCs50EmjtJyNLDcgTGSVNvcQ - while it's diesel focussed, all the information he passes on can be applied to spark ignition engines, too.

Hello Gord,

Thank you for your reply. Love Gale Banks and his channel , he's the reason I built my own CAI . Manifold density and air density talks are awesome. I also saw some clutches for the hellcats they look interesting. I really think that it is possible to use a dual action turbo so to speak instead of the super turbo Gale does and that I thin Nissan also did in the 90 in Japan.

A friend of mine made it on his Mitsubishi Pajero Evolution two years ago - it is activated by pushing a button just like air conditioning...

Aisin's SC12 supercharger had/has an electromagnetic clutch integrated. IIRC it was what was used on a couple 4AG powered Toyotas, including the MR2.