Cummins Diesel Forum banner

4" vs. 5" exhaust

79K views 46 replies 30 participants last post by  holydiver89 
#1 ·
Was looking at uprgading my exhaust to 4" or 5" from the turbo back, not really sure which size to go with. Was also wondering which brand to go with???I was looking into magnaflow.




2006 2500 4x4 sport, short box
bonestock
 
#6 ·
I have owened 4 diffrent systems and to be honest FarmboysDiesel has a fantastic kit. Very affordable and the fit is perfect. I choose the 5" as it is not as loud as the 4". It is loud but is allot deaper in sound. I also opted for the 6" tip which adds that tone to it..
 
#9 ·
i just put on a 5 inch Turbo back MBRP and i love it, not too load but you can definatley hear the truck roar.
 
#13 ·
Call Gus @ Farm Boy Diesel, the 5" straight sounds awesome, and i installed it myself in about an hour... And yes he has the best deal anywhere, call him up.
 
#17 ·
farmboysdiesel: Can you pm me a price on a dual 5" kit with 5" dp, for my 07 Ram 2500 QC/5.9lt/4x4?
Also do you offer a 5" dp with 4" exhaust, actually pm a price on both, please?

Which is louder btw, im looking for something subtle!

Thanks!
 
#18 ·
Ok Guys....Dumb question here, For all you turbo back installs, what do you do when its time for an inspection? Does your state not require a cat? Just curious. I would fail inspectiojn here in DE and would be required to reinstall the cat in a few years. Thanks :CRY:
 
#21 ·
#22 ·
In Delaware we go through a vehicle inspection every 2-5 yrs for new tags depending on vehicle age. They check all vehicles for Cats....You fail if you dont have one. Luckily im tagged for another 3yrs but will eventually have to deal with inspection!!!!It sucks :RANTIN:
 
#27 ·
You're wasting your money on a 5" system unless you're over 600 HP, just change the muffler or straight pipe it and put the money you save towards something that will actually GAIN you something.
 
  • Like
Reactions: Igoo65
#28 · (Edited)
I run the Magnaflow 5 inch into dual 4 inch exhaust on my truck and saw a huge difference in egt's over stock 4 inch with no muffler or cat. When I had the 4 inch and just an Edge on my truck I could start off in second gear getting on it and by the time I was getting into sixth it was defueling at 1400 degrees. I put 5 inch on it and it rarely gets over 1200 degrees with just the edge. As far as power goes I don't really know that I gained much. I mainly put it on to help lower egt's
 
#34 ·
5" is 25% bigger than a 4inch. in the airflow characteristic world that is immense. especially for you 3rd gen guys who can actually fit 5" downpipes, it is substantial. im not gonna claim hundreds of * egt drop, but it is a substantial difference nonetheless, and i dont sell exhaust.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top