2.5In Or 3In Exhaust Tubing

[firehawknwv]

Well now that I got my Doug Thorley LT's installed Im ready to finish the rest of my exhaust. Currently I have Magnflow x-pipe 2.5 in/out and 2 Magnaflow 2.5/2.5 round mufflers that were gonna get installed. So I was gonna go 2.5 in all the way from the headers back. I originally was gonna go the same round but with 3in all the way back. Ive been told that dual 3in is too much for our trucks with just bolt on mods. I figure dual 3in would be perfect for these trucks as I figure there will be enough backpressure still but enough flow to get power and good sound out of. I will be installing a TBSS intake w/tb, 44lb injectors and efans and currently I just have a Volant CAI wiht the LTs muffler and a tune. So if anyone can can help pint me in the rigth direction Id appreciate it. I searched but didnt come up with much of what I wanted to know.

 

 

I do plan on a cam and stall soon so thats why Im instaling the 44lb injectors now with the TBSS intake.

[Hankg42]

I'm sure some of the real performance mavens will chime in, but I'm pretty sure I remember a post on here stating that 2.5" is all you need on our trucks, and that 3.0" doesn't buy you anything. I hope I remember correctly. Maybe you can find that past post.

 

Edit: Here's one I found... http://www.silveradoss.com/forums/index.php?showtopic=61164

Edited August 6, 2010 by Hankg42 (see edit history)

[firehawknwv]

Ok, thanx. The funny thing is the 2 magnaflow mufflers that I have were Zachmans who posted in that thread you posted, lol. He talked about ditching them after his headers install and thats exactly what he did so I got them from him. Also stated in that threadis that 2.5 in is enough for NA trucks so that helps, but Im sure others will chime in here also.

[RevolutionRaceWorks]

2.5" will take you where you want to go N/A without doing any further mods to the heads or bottom end or adding boost. I run bigger everything but I also have more CI and more compression than stock and I do alot of boosted setups. But for where your going I think the 2.5 will do you just fine.

[zachm89]

when i sold you that setup and put my headers on i went to a true dual 3" setup and i wasnt pleased with it at all...the truck just couldnt push out enough exhaust to produce a good sound or performance. Honestly id stick to the 2.5" duals, i think youll be alot happier that way. I quickly got rid of the dual 3" and went to a single 3.5" exhaust that im running now and i couldnt be happier. Id stick with the dual 2.5" if i were you.

 

Zach

[firehawknwv]

Thanx guys.

[BgRd1]

i think a 3.5 in single tube setup would sound awesome and give good performance as well. another thing that makes a difference in power when it comes to exhaust is the typ of muffler, not necessarily the brand but the type. some mufflers with dual in/out have straight through designs or "X" designs. some have "S" design.... choose the one with the right design for your setup and the sound will also be better. not enough backpressure= lose tq and sacrifice sound, backpressure but not too much= good tq and hp #'s and awesome sound!!!

 

good luck and post pics when you get it finished... im looking for ideas for my exhaust setup as well!!!

Edited August 8, 2010 by BgRd1 (see edit history)