Originally Posted by RCZ (Post 407761)

Alright so after reading a bit from reputable sources. AKA Garrett from the stuff that Silo showed us.

Bigger turbos make more power per the same psi for two main reasons:

1) Bigger turbo will put less heat into the air and therefore the air is denser. More air = more power

2) The actual CFM of the turbo is meaningless. What matters is how much of that air is actually going into the engine and being used. There are restrictions that keep all the air from getting to the combustion chamber, the main one being backpressure from the exhaust housing of the turbo. The smaller it is the more backpressure, the less air that can flow through the engine, the less air that can flow INTO it in the first place and therefore less power. So bigger exhaust housing means less backpressure, meaning more air in, meaning more power.
The logic seems to be that it doesnt matter if the turbo can flow an infinite cfm, if the engine can't make use of it. The less backpressure, the more the engine can use, the more power it can make.

So how does this all apply to the SC vs TC dilemma?

I would say its the same thing, more flow through the engine means more power. So why do manufacturers recommend sticking with 2.5" piping rather than 3" piping on an SC? Because the sc doesnt flow enough in the first place to cause a 2.5" exhaust to become an obstruction??

Originally Posted by shumby (Post 407894)

tell me again how discuessing turbo's for the last 3 pages is on topic to this thread?

Originally Posted by shumby (Post 407912)

MOds/admin. please move the turbo posts to there owen thread. There is useful info here but all these posts will take away from the point of this thread. (GTM's SC) makes it hard to search and find info in this topic

Originally Posted by budakai (Post 408039)

I think it's all useful information for vets and noobs. Shoot 70 pages of this thread alone is just filled with us begging GTM for information on the SC kit. They should remove that before moving this useful information.

Originally Posted by Zsteve (Post 407872)

This makes sense, with my 4 cyl turbo, when we just upgraded theintake and Down Pipe we saw huge gains as more air was flowing in and out. When I chipped the ECU I also went 3 in TBE and with the small turbo on the car I hit full boost @ 2500 rpms and actually had more TQ than HP on the car. I had over 300 TQ and about 260 HP on a 4 cyl FWD car, it was fun to feel all that TQ. Since the turbo does create its own back pressure we could go larger on the exhaust (to a point of no return of course) but I guess NA cars use the exhaust to create the back pressure.

Originally Posted by shumby (Post 407912)

MOds/admin. please move the turbo posts to there owen thread. There is useful info here but all these posts will take away from the point of this thread. (GTM's SC) makes it hard to search and find info in this topic

Originally Posted by Buddy Revell (Post 407965)

Because the compressor side of a turbo and a centrifugal supercharger are pretty much the same, unlike a roots-type/twin-screw supercharger. Understanding one will give you a greater understanding of the other.;)

Originally Posted by BRUSSO (Post 408009)

to me the point is simple..... if you are making a small amount of boost(3-5lbs) the stock exhaust and cats can handle the amount that is trying to be pushed out. However, the more boost you make (8-10lbs) the more trouble the stock exhaust has . So by removing the restrictions in the exhaust you will see higher gains with higher boost levels.

Originally Posted by Zsteve (Post 408079)

You didnt get the car tuned after swaping the turbo to a bigger one?