TT Harpipes posted by Kyle (StrictlyZ.com) on January 16, 2003 at 07:35 PM
Message
and on the piping on the throttle bodies should not reduce like that. You can use a coupler that increases to the size of the opening of the throttle bodies. But don't have them expand and then shrink back down. Also the hard pipes heading the intercooler should not be larger than than its connecting pipes. Basically your pipes are too big. Use 2" for the ones going to the intercooler and 2.25 for those going to the throttle bodies.
Here is an example of some pipes that are on my car and I think they do a good job.