OK, picked up a 4" down pipe (finally) for my '03 and does not mate up. The flange is bigger (obviously) on the 4". What is my solution? Cut off the flange off my old down pipe, and weld it on the 4" or??????

 

That's interesting - I thought the 4" 325hp pipe would fit. I have a 4" elbow and a straight piece of pipe waiting for me to make a downpipe bit I though I might just buy a 325 pipe. I guess I'll cancel that idea. I'd weld the 03 flange onto the 4" pipe instead of replacing the cast elbow, too. Craig

 

That is my plan of attack so far, unless someone has another idea that works that is easier that my plan.

 

You should be able to purchase a 4" exhaust elbow from a 2004.5 & newer and place that on your turbo. Then your new 4" downpipe should fit like a charm.

The 2003-2004 models have a 3 1/2" outlet but the 2004.5 & newer have a true 4" outlet.

Maybe check Ebay, here on the classifieds or even a local junkyard....

HUMP

 

OK, thanks for the info. My wallet is taking a hit these past couple weeks (Walbro, TST, downpipe)

 

SSminnow,
I got a question, does your exhaust pipe neck down just past the marmon clamp or is non tapered?
I have a early built HO and it appears to have a 4" elbow, the exhaust pipe is tapered just beyond the clamp.

MikeyB

 

OK, ran out to the garage to check, and......yes it does. Where the down pipe un"clamps" from the exhaust elbow, on the down pipe itself, for about a 1" to maybe 1 1/2"'s is bigger, then there is weld, and it bottles back down all the way until I made the cut and put a 3 1/2" to 4" reducer in place and put in a 4" exhaust from there back.. But the new Down Pipe I got is 4" all the way (not sure if it is a takeoff or aftermarket) but where it bolts to the exhaust elbow, the downpipe is 5" across, and my stock downpipe that I just took off is 4 1/4" across the same area. Even the band taht holds the stock down pipe inplace will NOT fit onto the new 4" downpipe I got, so, going to call the dealer and see what they have....