ARH Header Installation

vettelovralexand · February 13, 2012

Well, this past month, dad got bored with the stock exhaust sound on his 2011 NHT 4wd CCSB Silverado and after discussing the options for 3.5 inch exhaust with me, I talked him into trying a set of ARH LT headers with cats. So, I called and purchased a set of their 1 7/8" primary headers for him. I ordered them on Feb 2nd over the phone and he got them on Wednesday the 8th. I was travelling home this weekend, so I contacted Justin for a tune update for the headers and made my install plans for Saturday. When I arrived to his house Saturday morning, it was rather cold...think high teens with a nice 10 mph wind. So, rather than work on the concrete in an open pole barn, we made a trip to my uncle's house and used his heated shop which also happens to have a 2 post lift. So we got started around noon pulling the factory pieces off only to discover 3 out of 4 of the factory O2 sensors were cross threaded at the factory. With a lot of love we got them out and luckily we were able to use a die to recut the threads. Not only this, but one of the 6 bolts (3 per side) holding the factory Y pipe to the manifolds was cross threaded also. Despite the hang ups, we carried on and dropped the transmission crossmember to pull out the factory Y pipe uncut. It took me ~1.5 hours to get all the factory pieces out and ready for the installation of the new headers. I began unwrapping the ends of the pipes in order to put them into place, only to find out that the back of the new Y pipe was not the proper connection to mate up to the factory exhaust...After a quick call to Nick, he informed me that the intent was to cut the factory end off of the Y pipe, slide that into the expanded rear section of the ARH Y-pipe and then bolt the system together using the provided 3.5 inch clamp and the factory clamp both. I didn't care for the answer, but agreed and so I continued onward and installed the headers. Fitment was excellent and I didn't even have to pull the plugs out in order to carefully slide the headers into place. There was also no interference with the steering shaft bolt like I had heard several people mention. With those bolted up, I installed the two pieces of the Y pipe while dad worked on cutting the flange off of the factory Y. This is where we hit a snag... the factory Y pipe has ~1 inch of straight pipe before the 3rd cat. This isn't anywhere near enough to seat fully into the flared and cut 3.5 inch section provided, so at best there would be a leak path from the cut slits. But, to top it all off, this would also be too short to reach the factory cat back exhaust without really pulling it forward. This didn't make anyone happy, but we carried on and got everything installed except for the connection to the factory exhaust. Another call to Nick put my mind at ease, as he agreed to ship us the connecting pipe (even if he had to make one) so that we wouldn't have to go to a muffler shop and get inferior piping which may rust to complete the system. So, slightly defeated we now had to drive home ~45 minutes with open headers. Needless to say, the truck sounded good, but was exceptionally loud. We did throw a fault code on the way home...but it was my fault as I had been distracted toward the end and forgot to reconnect the back, passenger side O2 sensor. Other than that, we parked the truck again in the garage and he is now patiently waiting on the connection pipe to show up, and the tune update to arrive from Justin. Hopefully these will be in soon and I will be able to travel home again and give an updated status. P.S. The truck now has 789 miles...not a bad way to start.

jdubub · February 13, 2012

Definitely keep us updated. I've been debating LT's as well.

vettelovralexand · February 17, 2012

Talked to dad yesterday afternoon. He said he received the part yesterday (apparently only because the UPS guy wouldn't leave it without a signature) and said that the part they sent appears to be the correct flange with at least a foot of additional 3.5" pipe. Also finally got the tune back from Justin on Tuesday. Hopefully I will be home to take pictures of the completed install soon.

jdubub · February 17, 2012

MedicPilot · April 15, 2012

What was total cost of parts/materials? Was considering doing LT's on mine as well.

STINSAN3 · April 21, 2012

Update?

vettelovralexand · April 29, 2012

Hey sorry guys, long time no time on the forums. Been pretty busy at work and I hate using the phone for typing. Anyway...got the piece cut down to ~4.5 inches to bridge the gap between the factory exhaust and the new Y pipe. Started the truck up and it idles like stock. Probably wouldn't be able to tell they were there if you weren't listening. Got the new tune from Justin installed and went out for a test drive and it felt really good. Transmission shifts smooth and truck pulls strong. Makes a little extra noise when you are hard on the throttle, but still could pass for stock to anyone who didn't know any better(quieter than the corsa sport and intake on my truck). All in all, I can't say I can tell a big difference in the performance of his truck before and after, but his feels considerably stronger than mine already and he hasn't even really broken the truck in yet. I think it still has ~810 miles on it now. I did send the tunes back to Justin to have him look at them again and see if he could raise the shift points a little and maybe make the tune a bit more aggressive because this truck will probably not pull anything since dad still has 2 duramax trucks for the real farm work. I'll see if I can update again with pictures when I go home next and maybe even a video if I can get some seat time.

@MedicPilot: We just had to purchase the headers themselves from ARH. I called and talked to a couple people, but the salesman ended up letting me have the headers for 1500 shipped to the door. I reused all the factory gaskets, bolts, and sensors in the swap, so no more money than the purchase price unless you have someone do it for you.

vettelovralexand · November 1, 2012

Update: The truck feels significantly stronger after the tune update. Pulls harder to the top than it did before and the raised shift points really made a difference. On a secondary note, I picked up a procharger kit for it this week and should be working to install that while home for deer season or potentially over Thanksgiving. Working on getting another tune update from Justin now for the base tune along with new plugs, a new crank bolt (to replace factory after pinning) and the air fuel ratio gauge and pod now. Should be a lot more interesting after feeding it a little boost!