Hey guys I'm going under my 97 1500 5.2 4x4 so I can fix a couple exhaust leaks. And I was figuring, while I'm under there I may as well do an H-pipe. Reason being, I don't see where it can hurt at all, and I have just enough stainless laying around to do it. My question is where should I locate it?

All my exhaust work has been done by the same shop, but I feel as though it was rushed due to the placements of my 18" glass packs and the cats.
The first cat comes pretty much off the manifold, before the cross member.


After the cross member is the second cat and the two glass packs.



Everything being offset in it's own way. Should I do the H-pipe in front of the glass packs, in between the cats? I figure that'll be the easiest place. I just don't know if there's any performance gain or whatnot with the placement being between cats and mufflers, or just maybe after the cats and mufflers? Any insight would be great.

 

H pipe should be ahead of the pre-cat O2 sensor.

 

"just to double check before I hack away at my exhaust" basically off the manifolds before the cats?

And I would assume the easiest way to make my holes in the side of the pipe would be, use a starting punch to make my mark and get the right size diameter metal hole saw? And for the H-pipe piece, what's the easiest way to get the "half circle" so it's a good fit over the parallel pipes?

 

Yep.

using a hole saw, without a jig of some sort to hold it in place, is gonna be a pain. Got a torch?

 

Yeah, Oxy/Acetylene. Just have to fill the acetylene tank monday. What's your thinking with the torch?

 

I generally just blow a hole slightly larger than what I really need, and then fill the void with the electric welder. It isn't always 'pretty'... but, it works fine.

 

Agreed, saves time too. Thanks for the help HeyYou.

 

Shouldn't the o2 be in the center of the H ? Or X for that matter.

 

That would be ideal, if the H pipe is SHORT. For a X pipe, that would be perfect.

 

Yea, but if you do that isn't the o2 only getting info from 1 bank ?