Difference between a roots and a twin screw

toolman · 11-20-2005, 05:21 PM

Ive seen some stuff on Twin screw blowers and dont really know much about them. I was wondering what the real difference between the two are. Dont they both use twin impellers?

11-20-2005, 06:06 PM

they are both one in the same, usually the difference being the internal gearing.

b_a_betterperson · 11-20-2005, 06:39 PM

Quote:

Originally Posted by toolman

Ive seen some stuff on Twin screw blowers and dont really know much about them. I was wondering what the real difference between the two are. Dont they both use twin impellers?

Roots blowers have straight-cut impellers -- while twin-screws have interlacing helix impellers. The twin screws are a lot smoother under acceleration -- while roots blowers tend to make a thumping noise as the amount of boost fluctuates.

Here's a nice article discussing blower basics: http://chevyhiperformance.com/techarticles/49378/

11-20-2005, 06:56 PM

BUT, both are twin screw compressors and both rely on gearing to produce their boost.

b_a_betterperson · 11-21-2005, 12:30 AM

Quote:

Originally Posted by big_mike

BUT, both are twin screw compressors and both rely on gearing to produce their boost.

I hear ya -- but the difference in impeller design results in a different classification in my mind. With the twin screw, the air delivery is smoother and much cooler. Don't have the time to follow it -- but I think the NHRA banned twin screws in the alcohol classes for a while because they made for such a difference in performance -- and that ban was specifically for the impeller design.

Steve A · 11-21-2005, 08:00 PM

A "Roots" is an air blower and compresses in the manifold, twin screw compresses the air in the blower itself. Twin Screw is much more efficient and heats the compressed air less.

AndrewZPSU · 06-08-2006, 01:00 PM

Yay for screwing twins!

HTRDLNCN · 06-08-2006, 02:27 PM

Quote:

Originally Posted by Steve A

A "Roots" is an air blower and compresses in the manifold, twin screw compresses the air in the blower itself. Twin Screw is much more efficient and heats the compressed air less.

exactamundo...
totally different design even though they look similiar..
and ALL superchargers rely on gearing even centrifugals...

The_Goat · 06-12-2006, 01:50 PM

So is there a twinscrew kit out for the GTO yet?

Robertr2000 · 06-12-2006, 07:33 PM

Quote:

Originally Posted by AndrewZPSU

Yay for screwing twins!

Twins?!?!?