turbo question

Gossy you answered your own question!

that's my point. Why spend $400 upgrading an exhause system then?

Hmmm - a debate on gaseous dynamics - stand clear for an avalanche of science Gossy ! My humble thought would be that as the gas cools down the exhaust could actually be proportionally reduced towards the rear, without ill-effect... which means that while that would be silly, your hypothesis must be correct !

What size is your turbo outlet? Often the size of the turbo outlet is larger than the exhaust diameter. Also your exhaust may have a restrictive dump pipe and catalytic converter. I was also informed a 3" would be even less restictive but depending on the flange size on the cat depended on if you could go up to this size. The less restricive the exhaust the easier for the turbo to spin up. If it's restrictive then the turbo fights against this and doesn't spin up as quickly. There's a post on Outerlimits in the 4x4 tech section with an exhaust guy there answering questions. I did a post but ended up giving him a call as well for more information.

Leroy

Hi Gossy, I just had a 3" system fitted to my 12HT, the difference it made was quite noticeable. It did have a standard system on it and I would imagine that it would have been quite restrictive, opening it up has provided a quicker boost effect resulting in improved performance.
I would highly recommend it!

If it didnt do anything the pipe would be really small from the factory. Look at sports cars they all run bigger exhausts because its proven for horsepower gains.