RXDawg

None with any the kit as far as I remember. Did modify the y pipe by cutting off the flange and welding on true duals. On the truck comes a stock flex joint I do believe. When I ordered my headers/pipe AR said they were only offering the pipe in one configuration which wouldn't mate up to newer trucks flex joints.....if I remember correctly is was they had a flange with two bolts and some of the newer trucks were being produced with 3 bolts? But that was 2 or 3 years ago and I would bet the problem is solved by now. It's really a small problem anyway.

stg313

I have 1 3/4 OBX headers with a Y pipe that I paid only like $520 for. The general fit is about 90%, I just had to have one of the connections welded. Considering the money I saved, I really can't justify ARH headers. But thats just me.

91Z28

I went Kooks 1 7/8" and couldn't be happier, great header and construction. They even have a spike in the collectors.

11Silvy

I went with ARH 1 3/4" catted-Y, fit and finish was 100%. SOTP was very noticeable. Merge collectors and spikes are included of course. Im 100% satisfied.

http://www.freeimagehosting.net/i55gr

JetBlack98Z

iTrader: (9)

I went with Pacesetter 1 3/4 Coated headers on my truck 372$ Shipped to my door, It took me about 3hrs to swap out the stock manifolds with the LT's, I couldn't be happier. The Fittament is perfect, no clearance issues whatso ever.

Went with a Custom built 3in Y-pipe utilizing a Flowmaster Dual 3in to 3 1/2in merger into a big body Magnaflow muffler, there is some drone, but it is definitely managable.

Good luck with whatever you choose.

Here is a video after I installed the headers, the truck was untuned at this point (No cats)

2011 GMC Sierra 6.2L Pacesetter LT's Magnaflow SI/DO Muffler - YouTube

BrutalSierra

iTrader: (1)

I am going to try the Cal_speed 1 7/8" long tubes when they release them. Kooks and ARH are a bit expensive for my taste. Headers have got so damn expensive! I understand there is more of a R&D process instead of just bending tubes to fit flange and body style.

It seems like the high part prices for the vettes has bled off to most GM products.

being i'm 29 with a mortgage,kid,2 car notes I think i'm going to budget build my truck.

Wish i could afford those kooks though, they sure are pretty.

Vegas Panton

Other than price (which can be very important) everyone seems very happy with their headers. Have not heard of any real fitment problems.

97 Z Me Go

iTrader: (11)

Well I beg to differ on the supermaxx headers. I just bought and went to put them on tonight. 2010 denali awd. Needless to say it never made it on the dyno for numbers. The y pipe fits like complete crap. I tried every which way to try to get it not to hit the trans and the trans cross member. I gave up. Will be taking them off and hopefully getting my money back. I put a set of kooks on my buddies 08 Denali fit like a glove. I will be waiting for kooks to build me a set. The y pipe had 09 inspection markings on it. Goes to show they must sit?!

Tootall

iTrader: (79)

keep in mind, Kooks and ARH will not rust since they're made from SS . . . vs the carbon coated Pacesetters.

97 Z Me Go

iTrader: (11)

https://www.performancetrucks.net/fo...d.php?t=496454

I personally did this test. Saw same results with and with out a blower. What we saw is the power stays the same past 4500 but downlow it makes more power. So yes the 1-7/8 are "better" these are AWD DENALI trucks. Tests were done same day within hours of each other for most realistic results.