So I installed my ARH headers and intermediate pipes with cats this weekend. The headers are beautiful, had to shave a little off the bell housing of the trans on the P/S and tweak the D/S motor mount heat shield. Picked up about .10 to .20 in my 0-60, sounds a little nastier when im on it and throttle response improved. The intermediate pipes were another story, they forgot to put the collector flange on the P/S pipe and they didn't fit right at all. Luckily I have a welder and enough exhaust pieces laying around I made em fit. Contacted ARH to let em know they didn't fit right, just for their purposes, dude said I was accidentally sent pipes for a 1500 6.0L application (SS/1500HD??), doesn't have an option to specify on their website?? and that they would send me new pipes for a 2500, I assume just because they forgot to put the flange on the one pipe so we'll see what happens with all that. Also had to remove two broken exhaust bolts, one had enough sticking out I could grab it with pliers. The other was actually counter sunk slightly in the head and i had to weld a nut to it, that was a pucker moment.

 

Looks good, only thing different I would have done is to use the oem gaskets instead of the gaskets supplied with headers.

 

Yeah I actually used a Remflex gasket, their supposed to be the **** so we'll see, got some longer ARP bolts and torqued em tof 20ft-lbs, not supposed to have to re-torque with these gaskets but I'm skeptical, doing a couple heat cycles then I'm going to verify/re-torque.

 

Weird they say 1500HD..... that's totally bogus as I share the same frame in the front, same diff and suspension, same LQ4 and same 4L80E as the 2500HD....... so what they sent won't fit a 1500HD either... just half tons with 6 liters and 60/65/70e's.

Be interesting to see what they send you

 

Well he said 1500 6.0L applcation, im trying to read between the lines. As far as I know the "1500" full size truck chassis with a 6.0 could be considered a Denali, C3, Vmax, 1500HD, or SS, they probably all have slightly different exhaust too so im also very curious to see what i get, i think its mostly a case of one size fits none. Although what they sent sure looks like it would match up well with a SS cat back exhaust system. Its just strange they dont give the option to clarify 2500 when ordering. They keep saying Y pipe, so I assume their probably going to send me the intermediate pipes for a new body style 2007 2500HD which Y down to a single after the cats. I've also installed one of those systems and it wasn't quite right either and needed some slight modification.

 

Also to eliminate the P/S cat and O2 bung that pipe would need to be about 3 to 4 feet longer with several bends, and the factory pipe/cat would need to be cut out like I did, so there's really no way I can see they offer a "direct fit" system for a 2500HD, unless your cool with leaving the factory cat on one bank of the engine haha

 

Looks great! I love mine.

 

A 1500HD is a 3/4 ton truck and shares absolutely nothing with the Denali, Vmax, VHO, SS, etc. They all have the smaller 6" channel frame, light duty tranny, 8.25" front diff etc. 1500HD is the same as yours underneath the front so if what you get fits your truck properly that might be an interesting thing.... and they are probably just clueless. Yeah.... no Y pipe... maybe that's just them being generic.

Yeah the passenger side I think is slip fit into the muffler.... mine is long since welded from leaking but the cat is like a foot ahead plus some goofy mushed piping over the crossmember lol..... well you are double protected on the passenger bank of cylinders haha.

 

Yeah I just meant ARH may group em all together, however on the item check sheet it it does denote that a "2500" needs and extra 3" clamp so we'll see what I get. Getting the D/S pipe to fit right was a total SOB, and I may have got a little carried away with the "ceramic" coating spray paint haha. I liked the way this thing sounded before, nice low deep tone, now with the headers its all that and a little bit nastier when im on it, and very little header tick noise, overall very pleased with how it turned out.

 

Is that an option to get a tru dual exhaust / collectors? maybe the trucks have more options that my ARH suv Y pipe...