Author Topic: Quadrajet on roots blower  (Read 3229 times)

Offline 6banger

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Quadrajet on roots blower
« on: March 05, 2012, 05:05:34 AM »
can a quadrajet be used on a small roots type blower
is it possible to boost reference the power piston?

Offline 73 Z28

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Re: Quadrajet on roots blower
« Reply #1 on: March 05, 2012, 07:49:14 AM »
On GM's turbo charged applications, instead of using engine vacuum to accuate the power piston, they used a small cam attached to the primary throttle shaft that would push up the power piston as throttle was applied richening the mixture. These carbs can still be found on ebay, craigslist etc.  All of the ones I've seen use the front inlet but there may be some out there with the side fuel inlet.

Paul

Offline Cliff Ruggles

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Re: Quadrajet on roots blower
« Reply #2 on: March 07, 2012, 05:27:46 AM »
Yes.  The turbo 301 Pontiac carburetors routed the vacuum to the power piston in from out outside source, so they could shut off the vacuum when the engine went under boost to keep from pressurizing the power piston. 

The cam actuated carburetors are very rare.  For roots type blower systems the carb can also be set up to run straight off the jets, where no power piston is used.....Cliff