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Has anyone here used or knows someone that used the roots style blower available from jim cook racing in their z or zx? What do you guys have to say about it? Im thinking it would be a nice thing to work twoards if your building up an NA and want to slap on some more power when your done. Also is it possible to set up an intercooler with a roots style blower? An intercooler would be nice since ive hear that roots blowers heat the air more than centrifugal.
 

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I got an e-mail after I posted on the same subject. I was told that only ten of these were made and that now all they carry is the manifold. It listed for $3300. Still haven't heard from Jim Cook Racing on it though. For all I know they still might make it.
 

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hey is there any setup out there for a centrigual superchager for z's? would it be very difficult to set up your own? just in case they arnt selling the whole roots style set up anymore.
 

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Available since August.

JCR has reintroduced the Supercharger system and it's been available since this past August. They now sell just the Supercharger and accessories separate from the EFI system so you can choose to use any EFI system you want.

Vortech has compatible Centrifugals, I've seen a few on Z's, but it's a fab-the-components-yourself kinda deal.

Roots blowers really heat up the air due to internal recirculation, and intercooling them can be done, it a bear though due to their "straight through" setup and design.
The Lysholm-Screw designed blowers made by Sprintex and Whipple lend themselves to intercooling much easier than the Eaton Built Roots blower. They take intake air from a port on the top, and discharge it from a port near the rear. The Whipple unit would fit on the A/C Bracket of a Z should ylu be so inclined. But both of these setups are Fab-it-Yourself systems, also. Stillen uses Whipple Screw Superchargers on his upgrades, and many of them are intercooled.

The drawback is Roots-Style blowers are pretty much limited in the boost you can get from them due to heating of the air. Lynn Burkhart up in Ontario Canada runs between 12 and 17# boosetd on his 240, and that car screams!
Given the intake temperature at those pressures with a Roots (about 200-270 degrees F) a Lysholm Screw would run at almost 30# of boost at the same discharge temperature! And the added benefit of being able to intercool the Screw adds even more possibilities.

Now before some engineer-theorist gets into the fray saying that pressure is pressure, and there's no way there could be that difference because of Boyles' Law or something let me say this:
The efficency of the roots is in the 30-50% range, while the Lysholm Screw is in the 75-88% range. This "stage factor" is an exponential part of the equation of gas temp in-vs-gas temp out for compressor calculations. I do it every day in theory and in practical application and know what I'm talking about. How many 100psi Roots Multi-Stage Blower systems do you see out there? None.
Screws and Centrifugals rule in higher-pressure applications.
And centrifugals typically have efficiencies in the 50-90% range, depending on where your flow rate and pressure hits the compressor map. So that's why you can have a turbo that puts out 280degree air at 15#, and another that puts out 175degree air at the same pressure.
Screws have a very linear response, and efficency increases very little as you increase the tip speed of the rotors to optimum, so they heat the air more on the low end of the rpm range, and less on the higher end---thats GOOD!
 

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Re: Available since August.

Do you run any of these applications? You have a great knowledge of the parts but do you know where to get any of them other than JCR? Jeez, I sound like one of those annoying little kids on t.v. that asks a million questions. Sorry. Anyway, if you could post some sellers sites or contact info that would be great.
 
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