Engine/Transmission (1998.5 - 2002) 4" 5" OR 6" Exhaust

[MTate]

I'm going to build my own system . Lower temps is what I'm looking for . How much differance is there in 4,5,6" ? I priced the material I can get 10' of aluminized 4" , 4-45's and a 90 for $135 vs $400 or more. I figure I'm a Union Pipewelder by trade and have all the equipment to do it with . Also what about the muffler and cat leave on or off ? What gains can I get. Thanks



1999 Auto 4x4 Q/C Bone stock . 137,000

27' Sportsman F/W

 

[Cummins724]

I'm going to build my own system . Lower temps is what I'm looking for . How much differance is there in 4,5,6" ? I priced the material I can get 10' of aluminized 4" , 4-45's and a 90 for $135 vs $400 or more. I figure I'm a Union Pipewelder by trade and have all the equipment to do it with . Also what about the muffler and cat leave on or off ? What gains can I get. Thanks



1999 Auto 4x4 Q/C Bone stock . 137,000

27' Sportsman F/W

It matters what sound you are going for... . the 4" exhaust will flow well enough for 600hp. I have a 4" exhaust sitting here that was installed on my brothers Duramax truck for a month & removed to go stacks. It is from the muffler back. I'm sure it would work on a Dodge... . it looks the same. It would save you time & I think I have a 4 inch down pipe for a stock turbo too. I like the sound of a straight pipe ctd... . the turbo whistles loud between shifts, but I also have a brand new muffler 4" from Summit Racing if you are interested.

 

[AFarmer]

I'd say go 5in at the max. A 6in would be way way big. If you do some hunting you can find a 5in kit for a pretty good price.

 

[Forrest Nearing]

if you're going to stick w/ stock size tires, go 6" why not?



my 5" is tight w/ a 285 in the spare location. I'm 5" all the way back and 6" after the spare. if I could have fit 6", I would have

 

[LEPage]

4" sch. 5 tubing would make a nice job. Just hire in to a food or high purity job & shop around. Some slick 2 pass beads walking the cup would look really sweet. What local are you out of?

 

[MTate]

Thanks for reply. My 5er rubbs already [ flipping axles today]Plan on staying stock meat . I'm going to start building it up . But want to start with exhaust and breathing system . Sound what can't hear you , doesn't matter . I will make it 5". What about off turbo reduce it down to stock 3" just cut and weld part of stock down pipe? What about muff and cat ? On or off? I'm out of Dallas L. U. 100 brother Page. But set up home in Waverly, Ohio.

 

[OPoole]

With a stock turbo outlet you starting out 3" downpipe will be 4" then 5"or 6" the bigger the exhaust the closer to moving parts and frame. Plus the bigger the downpipe the bigger the pain in the but for working on your trans. bigger not always better if you had twins i would say 5".

 

[JVackiner]

I kept the stock exhaust pipe but replaced the cat and muff with a straight pipe. Sounds great and I don't have the drone that I have heard mentioned in some other posts.

 

[OPoole]

Thanks for reply. My 5er rubbs already [ flipping axles today]Plan on staying stock meat . I'm going to start building it up . But want to start with exhaust and breathing system . Sound what can't hear you , doesn't matter . I will make it 5". What about off turbo reduce it down to stock 3" just cut and weld part of stock down pipe? What about muff and cat ? On or off? I'm out of Dallas L. U. 100 brother Page. But set up home in Waverly, Ohio.

It would be easier if you got a 4" downpipe and a 4"-5" reducer and build from there.