Hey guys..I was maybe wondering if anyone could explain how the roots style s/c'ers work, as in upgrading capabilities and how the intercooler works on those? Honestly, I just traded my Cavy for a Cobalt, and the cobalt forums are not as great as this one, so since I had been using this forum so long, I was hoping you guys could still help me out. Thanx alot

Basically, there are two rotors in the s.c that always spin. They supply instant full boost when you mash the gas at any rpm (advantage of roots style blower). No spool time. That's why a lot of people (myself included) like them.

Your car came stock intercooled and is fine the way it is until you start putting smaller pulleys on the supercharger. The GM Stage 2 is a GREAT upgrade because it's more powerful than stock AND retains whatever warranty you might have. There are plenty of companies that offer different products and tuning packages. GM Stage 2 is the safest though.

Most people would agree that these blowers make a LOT of heat. I wouldn't go below a 2.8, maybe even a 2.9" pulley depending on your altitude. Your injectors can't keep up. You have to pull timing. It's more of a headache. Plus, the #4 piston suffers from extreme heat and not as much fuel as the other three.

As far as upgrading the stock intercooler. You could run another one in line with it to further cool down iat's, or use meth injection.

Hope that helped.

I agree with most of the above, the roots style does use 2 triangular shaped fans that constantly spin via your pulley on the end, unlike a centrifigal style, which looks like a belt driven turbo charger. The only real way to upgrade a roots style would be to use a smaller pulley (as stated above), which turns those fans inside faster.

As far as intercoolers go, I would not add another one, as the added airflow restriction would probably outweigh its extra cooling. You could look into a larger one, that fits in the stock location. The better option for the roots style supercharger is the type of intercooler that mounts right under the intake. I am not sure if this is available for the cobalts, at least yet. This is the best upgrade available for something like a Grand prix GTP, or impala SS that uses the same style supercharger on the 3800 motors.

As with any boosted application, you want to keep your exhaust backpressure down, especially at the "downpipe" area. A header, larger header to cat pipe, and high flow cat should do you some real good (as well as a cat-back system).

Of course most of this requires retuning, which you can do with HPT, unless you do the stage 2 from GM. The stage 2 kit will keep your warranty intact, but when they flash your computer, it locks it from being re-written, so no more upgrades after that.....

Stage 2 doesn't lock it after it's re-written...