Does size really matter with exhaust?

DIRTY DIRTY

Down and Dirty!
Dec 12, 2009
58
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Snyder TEXAS
I just discovered that who ever owned my truck previously murdered my exhaust. I've got pieces of pipe ranging from 3" to 3 1/2" to 4", no cats, and I have no idea what kind of muffler. Plan on getting a MBRP exhaust cause thats what I use to run on my Stroke, but what size? 4" or 5"? I've heard you don't need a 5" until you are pushing over 500hp, but eventually I plan on it. Will I loose performance until I get all my upgrades?
 

paint94979

Beer Nazi
Sep 18, 2006
11,715
8
38
37
I just discovered that who ever owned my truck previously murdered my exhaust. I've got pieces of pipe ranging from 3" to 3 1/2" to 4", no cats, and I have no idea what kind of muffler. Plan on getting a MBRP exhaust cause thats what I use to run on my Stroke, but what size? 4" or 5"? I've heard you don't need a 5" until you are pushing over 500hp, but eventually I plan on it. Will I loose performance until I get all my upgrades?

4inch exhaust is what i have on my truck:D which is around 650hp :D
 

DIRTY DIRTY

Down and Dirty!
Dec 12, 2009
58
0
0
39
Snyder TEXAS
Well! If you guys are pushing that kind of power out of a 4", I see no reason to go any bigger. Thanks. How about this though. What kind of difference would the stainless exhaust have versus the aluminized exhaust? Besides the price.
 

othrgrl

Diesel Addiction Owner
Mar 10, 2008
2,151
4
38
Wilmington NC
www.mydieseladdiction.com
I personally have 5" but even with my big turbo I only have a 4" downpipe and front pipe, so I highly doubt I would lose any power if I went with 4" the rest of the way back. I think the 5" sounds a little better - smoother and deeper in my opinion. Aluminized is typically fine since you are constantly keeping the inside covered in an oil based soot - but like Pat said if you are in the salt/rust belt I would consider stainless.
 
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dmaxfireman

'Can do' kind of guy
Apr 8, 2007
2,329
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CT
my aluminized 5" has held up alright so far. i'm in ct and they run a liquid calcium on the roads but i at least rinse off my truck if not wash it every time i notice they use it and i get that white film on everything.
 

A_T_Ver

Member
Jul 31, 2007
416
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16
I have aluminized 5" in the salt. So far it's fine. I think the 5" sounds better too.
 

mytmousemalibu

Cut your ride, sissy!
Apr 12, 2008
2,230
0
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Kansas
Have stock DP dumping into full 6" straight pipe that exits in front of the RR tire. Will be uping the DP size when it gets twinned and going to a stack but still 6"

.....Very loud, very aggressive :thumb: Everyone says from the outside when I floor it, no longer sounds like a diesel:rofl:
 

DIRTY DIRTY

Down and Dirty!
Dec 12, 2009
58
0
0
39
Snyder TEXAS
Hmmm. Well I guess I'll just see how much money I have left over after Christmas. I'm looking at $385 for 4" and about $550 for 5". I think I'll use the muffler delete pipe as well. I think they sound better straight piped.:coolspot:
 

othrgrl

Diesel Addiction Owner
Mar 10, 2008
2,151
4
38
Wilmington NC
www.mydieseladdiction.com
Hmmm. Well I guess I'll just see how much money I have left over after Christmas. I'm looking at $385 for 4" and about $550 for 5". I think I'll use the muffler delete pipe as well. I think they sound better straight piped.:coolspot:

MBRP 4" aluminized straight pipe is $259.98 shipped; with the muffler it's $283.03; a polished stainless 4" inlet, 5" outlet dual wall angle cut tip is $40.

MBRP 5" aluminized straight pipe is $388.09 shipped; with the muffler it's $455.08; a polished stainless 5" inlet, 6" outlet rolled lip angle cut tip is $65

I personally don't like the sound of straight pipe on a single turbo truck, I think it is too harsh and raspy at WOT and drones too much on the highway. The kits with mufflers are just as loud but more refined at WOT and don't drone nearly as bad if at all on the highway. I have a 5" kit with muffler and like it all around - deep, smooth rumble at idle, deep loud roar at WOT, and very little drone on the highway - although it does drone more now with the bigger turbo and I'm thinking about adding another muffler to it.
 
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