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Exhaust!!?

2K views 14 replies 8 participants last post by  Jordan_Likens 
#1 ·
I need to buy a new exhaust turbo back ... 4" or 5" and reasoning please !!?
 
#2 ·
Buy the 5" I've seen and heard enough of ppl on this forum said they would've gone 5" instead of 4" if louder exhaust noise is not a problem of course.
 
#5 ·
I have 5in on mine and it was straight thru for awhile but it was way to loud for me! Put a muffler on it made it quiet and didnt change the performance of it...I would say backpressure isnt an issue...
 
#7 ·
4" is all you need until you get to really high hp numbers. The 4" system flows cleanly. The 5" system has the exhaust tumble inside crating some turbulence. Basically the exhaust gases run into each other in a 5" system. Unless you are north of 400hp (maybe 600???) a 5" exhaust gives no advantage other than noise.

GAmes would say that going from factory to 4" made zero difference in any measurable way.
 
#8 ·
its all on what you personally want on your truck. With a stock turbo bp wont really matter that much. 4" is a good sound and not ungodly loud. 5" exhaust will give you a much louder sound and groan. Ive had 4" and 5" exhaust turbo back on both my 12v cummins and honestly dont really care which one is installed. Ide go with the cheaper one because 4vs5" is all about sound on a stock truck.
 
#9 ·
5in has bad drone in cab, so either muffler or resonator, is needed or do what i do turn the radio up a little more. she sounds great, noticeable idle difference when standing next to the exhaust, especially when its cold outside
 
#11 ·
If that exhaust is to loud for you check out this site. The FTE resonator has excellent reviews. The 30" version makes it a lot quieter than the shorter one.

Search Results - FTE Diesel
 
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