Does the T3/T04E and the T3/T4 have the same turbine housing or are they different? I know some turbos have the internal wastegate, which I don't want. Also what does the trim number, such as 57 refer to, I can't find any info on specifics. I've read of the S, V, etc trim on wheels, but not 57. And finally is there a lot of difference between a .48 and .63 A/R turbine housing in terms of spool up and max HP. I know the larger the A/R the more power it will make, but does it make that much difference in lag from low rpms.

 

.63 AR should be fine on spoolup. There are two different kinds of turbine housings, ones designed for use with internal and external wastegates. Most people (me included) have the one for an internal wastegate, but you just use an exhasut flange that blocks off the stock wastegate port for the downpipe.

 

Yes there is a difference in the .48 and .63, either way I think you would be better off with the .63 street and track.