Downpipe

[CAROLINA CUMMINS]

Howdy fellas,



What I would like to know is; where can I get a 4" downpipe for

when I get my custom exhaust made I want it to be completely

4". or would it be best to keep the stock downpiper have them make me one (my local shop) ? I was thinking on just turning the exhaust out in front of the rear wheel I LIKE it LOUD. !!





Thanks Steve

 

[hdm48]

Check with Piers at PDR. I believe he has them or can get them. And the stock down pipe is too small if your doing some bombing. A larger pipe will let the turbo spool up faster and cool it off some.



--dave--

 

[Titan]

I checked the Piers at PDR and they do not have one. As you can tell I am also looking for the same thing. Do most people just go 4" from the down pipe back. I check a local muffler shop and they said they would install 4" pipe and a high flow muffler from the down pipe back for $260. Does that sound reasonable to everyone? I would really like a 4' down pipe that connects to the 3" turbo outlet. Can anyone help me?

 

[Bob Wagner]

check with Rip

there have been rumors floating around



www.sourceautomotive.biz



he working with another 1st genner on this project

 

[Titan]

Bob the Rip system you run has a 3" down pipe and 4" from there back. How do you like it? Did you notice a difference in performance? My father has worked for Cummins Northwest for the past 35 years and he is skeptical? He feels it will help with EGT but will not contribute to noticable horsepower. What are your thoughts?

 

[Old Smoky]

Rip and I installed his 4" system on my rig the first of the month. It is 4" from the downpipe back, with an Allied truck muffler. I didn't buy Rip's downpipe because it was not an upgrade from stock. My downpipe was in good shape so he recommended that I save $75 and keep the stock one. I don't know why it doesn't come with a 4" downpipe, his systems for newer rigs do.



I noticed a little more zip with the 4". Boost increased about 1. 5psi and comes on much faster, and high rpm responsiveness and power is improved. EGTs are also down some. I don't know how much of a difference a 4" downpipe would make. It might be noticeable?



Mike