Does anyone make a 5" down pipe for the 03/04's ??? Our is a 4" down pipe all that will fit?? How many places make the 5" exhaust for the gen3's??

 

No I dont need a 5" DP I just thought it would be cool and maybe change the sound even more...


[quote author=BIGCUMMINZ link=board=49;threadid=23277;start=0#msg218459 date=1070596386]
what do you need a 5" downpipe for.......and no youd need a different turbo housing ;D if you putting out A TON of HP then cool but i dont know of anyone
[/quote]

 

The stock downpipe is 3.5"

I would not go bigger than 4" right off the turbo. Go down about 2-3 feet before flaring to 5" or you will hurt your turbo spoolup and notice less power on acceleration.

Vaughn

 

Thanks for the info,,


[quote author=Vaughn MacKenzie link=board=49;threadid=23277;start=0#msg218510 date=1070608648]
The stock downpipe is 3.5"

I would not go bigger than 4" right off the turbo. Go down about 2-3 feet before flaring to 5" or you will hurt your turbo spoolup and notice less power on acceleration.

Vaughn
[/quote]

 

The turbo housing elbow is 4". The OEM down pipe starts at 4", then quickly necks down to 3.5". The OEM exhaust expands to 4" again just after the muffler. I've heard several opinions that one should stick with the 3.5" size down pipe, unless going nuts with hp/tq increasing goodies.

 

I dynoed before and after putting a 4" on and while I didnt gain any power I didnt lose any either. Spoolup was slightly quicker. Truck doesnt sound like it has a foot shoved up its keister any more which is important to me at any rate.

 

When you installed the 4" down pipe, what other mods did you have at the time?

 

I was stock cept for gauges on the first dyno and had intake and exhaust on the second one. That is with an entire 4" exhaust, not just the downpipe.