Engine/Transmission (1994 - 1998) Straight pipe exhaust system

[JamesPhillips]

I would like to modify my 96 2wd p/u exhaust system to straight pipes, no muffler or cat. The local exhaust shops I've checked can't bend 4" pipe. Could anyone tell me if 3" pipe from turbo, split into a dual set of pipes would sound as good as 4" pipe? Also would I see any increase in performance?

 

[TomGolden]

Hi James, welcome to BOMBers Anonymous



I have a straight piped 4" system, never did anything to my stock 3", so I can't compare the sounds from personal experience, but I can relay what I have read on the TDR from other members who have done a sound comparrison.



Sound wise, 3" or 4" straight piped apparently is only a little different sounding. The 4" allows a little more low frequency tone, so it has a little more bass to the sound, more like a big rig. But, from what I remember reading, not a real significant difference.



Now as to performance. If your truck is bone stock, or only slightly BOMBed, say in the <300HP range, the common consensus here is that going straight piped really adds no performance benefit at all. If you are in the 400+ HP range, it can help reduce your EGTs a little, like maybe 50* or so, but even then, not a huge difference.



I removed my muffler purely for the sound, which to me is absolutely .



Enjoy the TDR and your Cummins!



Tom

 

[JamesPhillips]

Thanks Tom. My truck is bone stock except for a K&N air filter. I am mostly interested in the straight pipes for sound. I want the big rig sound. I love the truck but I'd like to get a little more power and was hopeful that this would help. I have a 28 foot 5th wheel and it sometimes boggs the truck down on a hill. I may go with the 3" pipe since it will be easier to find someone to do the work. Straight 3 or 4" should be pretty loud

 

[Deezul1]

Straight 3" sounds nice and the lack of muffler and cat help reduce EGTs. my local muffler shop replaced the muffler and cat with a piece of pipe for $50, no bends needed.

 

[Blakers]

James,



I had a 3" stainless straight pipe on my 95 and worked just fine. I figured I was running about 300 horsepower, but compared to my new 03 HO, I must have been closer to 400. Anyway, I think 3" is just fine.



Blake