Quote Originally Posted by chituntang
Dimension for the piping actually does not have a standard, but it actually makes your turbo's response and limit your max power. Small piping means easier to fill up, less lag. Bigger piping means harder to fill up, but more air to go in. So it really depends on your turbo setup. My hot pipe is about 2 inches and cold pipe is 3 inches. My buddy's GT2871 SR has a 3 inches hot pipe and 4 inches cold pipe. It is all about how much power you planned for your car.


Yea that part i bolded is just retarded. GT2871 is a small turbo and does not need 4 inch piping on the cold side or 3 inch piping.

the max you need on that turbo is 2.5 inch on hot side and 3 inch on cold side.

even GT42 turbos dont run 4 inch piping for charge piping of the compressor.

id love to see that guys setup and see the large reducer from 2/2.5 inch on the GT28 compressor housing to a 3 inch pipe.

your friend could reduce a substantial amount of lag with no loss of power by stepping down to properly sized piping for that turbo