Custom exhaust size?

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FranticMeeping

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Needing to redo the exhaust on 6.2, guy in neighboring town bends custom exhausts. Just curious y’all’s opinions on what size to go with? I believe it is 2 1/4” now. My old 78 K10 with a 350 had a nice sound with 3” and Red glass packs. Is that overkill for the noise police anymore? I did that 20 years ago when I was 19,
 

Frankenchevy

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Are you talking dual 2-1/4 or single?

Either way, don’t waste your money on mandrel bends. I makes no difference in performance.
 

Camar068

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there are exhaust calculators out there
 

Magna86

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2.5" nothing more and a good set of mufflers with pipes to exit the rear. Helps eliminate drone and getting black exhaust soot on the truck.
 

Blue Ox

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On my pickup, the factory build was dual pipes, 2.5" from the manifolds to the muffler, from there the tailpipe was 2.25". I can't picture any benefit to putting anything bigger than 2.5" on it.
 

Bextreme04

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Its a diesel, you aren't going to have any real benefit or awesome sound from a big dual exhaust. I'd probably just go with the cheapest decent exhaust, which means it would just be 2-1/4" dual exhaust with cheap turbo mufflers.
 

SquareRoot

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Stacks!
 

Blue Ox

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Its a diesel, you aren't going to have any real benefit or awesome sound from a big dual exhaust. I'd probably just go with the cheapest decent exhaust, which means it would just be 2-1/4" dual exhaust with cheap turbo mufflers.

Right. Also consider that bigger pipes on an engine that doesn't turn that fast slows the exhaust velocity, and with a diesel it pays to project the soot as far as possible.
 

Craig Nedrow

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1 7/8 headers to 3" pipes into Holley Aero chamber mufflers in front of the back tires, blowes the tire smoke most excellently sideways. I love the sound of the foe fiddy foe, also the reason I won't drive an electric vehicle.
 

Raider L

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Headers, the only way to go. 1 5/8" primaries into a 2 1/2" collector, 2 1/2" duals with Flowmaster mufflers as close to the rear end as is practical, exhaust pipes over the rear end, exit either straight out the back, or "highway style" turning out just after the rear tires. That's the way I have mine. This is for small blocks. Diesel, I have no idea. Would it be the same as a big block? Otherwise 2" primaries, to a 3", maybe 3 1/2" collector and the same parts, i.e. mufflers, tail pipes. Is that the way ya'll do it?
 

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