I read an article about using a wastegate in a centrifugal supercharger setup. To me it sounds like a great idea. You could set up the centrifugal to produce say 20 psi at red line but then set the wastegate to the psi you really want to run, say 10psi. This way you'd hit 10 psi at a lot lower rpm and then level out. Minimizing the lack of low end boost centrifugals are known for.

If I understand this correctly you'd need the wastegate before the MAF. You look at the Vortech kit the MAF is before the blower. To use a wastegate you'd need the blower first, then the wastegate and then the MAF. Am I missing something?

I've done searches and haven't come across much in the form of kits with this setup. I'd think this would be a hot street setup to gain low end torque.

Is anybody on the forum running this setup?

I would think that would take some major tuning to get the maf to read right under boost. sounds like a tuning nightmare, but perhaps thats the reason turbos are so tough to tune..

Thing is, it doesn't seem to me that the lag is all that bad.. It isn't like you shift into 2nd on a racetrack and have to start at 2500 rpm or something.. when you shift from 6500 you are already at like 3500 or 4k and have boost.. the only advantage would be launching from a lower rpm or having a little more torque in a higher gear when cruising. The major downside would be the parasitic loss of running a smaller pulley..

I agree that it would be a tuning problem. Although setting up a centrifugal for a blow through MAF isn't hard.

I wasn't thinking lag but your max boost at lower rpms. You have boost but it's low at 3000 rpm relative to your max boost which is at say 6500. The selling point of a positive displacement blower (which I'm sure you're aware of, I've read about your KB) is full boost right off idle. With a centrifugal it is rpm dependent. Nearly no boost off idle but it builds with rpms and continues till your car's red line. It's rpm dependent and keeps climbing so you have to set it up with your max boost at your red line.

If you run a waste gate with the centrifugal and are set up to run no more than say 10 psi you can spin the blower to make say 20 psi at 6500 rpm.
(disclaimer: totally made up numbers)
Just to throw numbers out, say you'd hit the 10 psi mark at 3000 rpm. At that point the waste gate would kick in and the centrifugal would maintain a full 10 psi from 3000 to 6500 rpm. Without a waste gate you'd have to set your car up to run 10 psi at 6500 rpm. At 3000 rpm you'd be making less than 5 psi.

As you said though, maybe it's a tuning issue. In my head this sounds like a great idea. With the waste gate centrifugal you'd get the low end boost like a positive displacement but the efficiency of the centrifugal at the high end.

This is the article:
Vortech Centrifugal Supercharger Wastegate Install - Muscle Mustangs & Fast Fords Magazine

The wheels are turning....

This has your name written all over it! With this set up you could have that low end Big Block torque you lust after!