Finished up the first 4" downpipe for the SideWinder GT1 kits that we produce. Later this week Ill have a full 4" exhaust ready too. What are the benefits of a 4" downpipe/exhaust combo you ask? Put quite simply, MORE POWER. With nearly double the cross sectional area, this equates to nearly HALF of the backpressure with the 4" exhaust system verse a 3" exhaust system. This should show quite significant gains, although I have destroyed my test-bed to compare to(lower compression, new valvetrain, and larger turbo).
Heres the pics










Just another option with our turbo kits The shop car will be up and running before the end of October, hopefully laying down some rather LARGE numbers...

 

That's f@#kin sweet! I may be switching to this sometime with a full 4" exhaust. Need to get mine tuned with the 3" at 8 psi first and see how I like it this way.

 

Do it up! Im still trying to find a relatively quiet, good looking muffler to use for the 4" exhausts; looks like I might have to do 4" straight under the car, then flare to two 3" mufflers, at least for those who care about sound. For everyone else, just resonators will work

 

Its sitting at the shop waiting to be installed!!!

 

Wow Tinker...if I ever decided to switch over to a turbo setup, you'd definitely be the person I'd go to...can't wait to see the dyno results...that downpipe looks great

For your next project, may I suggest trying to stuff one of these in there:

 

Thats why I only use LoveFab Parts!.... It just sucks that all of mine are custom!!!