cowboy717

i'm thinkin about straight piping the 02 i will be getting soon and gettin some things line up first, i've been hearin some things about the sizes of pipe, what is the difference, if any, in a 4" and 5" pipe??? will the 5 be louder? any advantages to either one of them??
thanks
cowboy

also wanna know what brand/type of gauges to look for, maybe a lil on the cheap side because i'm a college kid on a budget

micah

I just installed a 4 inch with muffler and it is much quieter and out performs (quicker and more boost and better egts) than my old 3 inch straight. yes, 5 inch will be louder than 4 inch. I ran the straight 3 for a while, and while I didn't really mind the noise, it was excessive and I felt guilty each time I left for work in the mornings. although, it may have worked to my favor since my wife insisted I get a new exhaust... hehe, "yes dear, I promise to get a new exhaust just to quiet it down for you"

for gauges, check this out...

http://dieselmanor.com/clearance.asp

also those guys do a great deal on a whole package with everything you need to setup your truck with guages.

STACKED

5" is not necessarily louder it has more of a deep throaty sound, 4" is more raspy and louder in my opinion.

BigBRUNO4

Good call! IMO, if you want to sound like a Peterbilt dump truck, go with the 5 inch straight pipe. Bleieve me, it sounds awesome. 4 inch is good but it sounds a lil too ricey. Just my $.02

GlennRMK

From what I'm told, you don't need 5" till your over 500 hp or so.

I run 4" turbo back straight pipe

Love it!

Willy91

If you want to sound like a Pete you need 6" stacks. The 5" is a lot deeper and sounds better IMO. But, if you are going for HP's you'll actually lose HP's with a 5" compared to a 4", it might not be noticable but it does show on a dyno. If you're not going for max HP go with the 5"

graphitecumnz

5" sounds simply sweet... and about the 500 hp, if you're worried about it, just get the truck to 500 hp and no more worries.

01smoker

Go ahead and get the 5". You'll love the way it sounds. I love mine.

tomgreentwin

I was told 5" might be too much for my current upgrades. 4" is a good step and sounds pretty awesome - especially with a 4 to 6" tip like I have. It's like you have the 5" exhaust already. 5" is deeper from what I hear going by my house on the newer trucks. Mine whistles a LOT more than the 5" systems. At 25-45MPH it is a good loud sound and also a solid whistle mixed in. Stacks? I don't know...we'll see. Not a lot of guys in this suburban area have stacks.