H-pipes

[BlueGhost]

I know there are a few people here running H-pipes. Did anyone install one on an existing exhaust system? I'm thinking of installing one on my truck and am wondering how much it will mellow out my exhaust. My exhaust has always been loud, but after installing the aluminum heads its gotten much louder. I'm guessing increasing flow and compression had something to do with it. Now it is loud enough to be annoying inside the cab.

I'd like to keep the basic sound of my exhaust system, just tone it down a notch. Will the H-pipe do that, or am I going to end up swapping mufflers? I have an H-pipe kit, but haven't but it on yet. If I do the H-pipe and mufflers I will likely take it to an exhaust shop instead of doing it myself.

[ICEMAN6166]

the location of the mufflers and the insulation or lack of in the cab has a lot to do with the loudness inside.

[Uncle Skip]

Chad. In the old days we used to shoot some spray paint on the exhaust pipes in the general area of the transmission, drove the truck or car and then looked for the "hot spot" where the paint burned off, and then located the H-pipe in that area.
See you and Hector at Pate.
U@ss

[BlueGhost]

the location of the mufflers and the insulation or lack of in the cab has a lot to do with the loudness inside.

The cab is well insulated, before I swapped heads it was fairly quiet inside the cab. It just got louder with the new heads, to the point where I think it will be too loud for long trips.

The mufflers are round straight trough chambered mufflers with no packing, they are similar to what GM used on Camaros and Vettes back in the 60s. They are close to 30 in long and positioned to the rear of the truck, ending just before the exhaust pipe bends to go over the rear axle.

Just trying to figure out how much an H-pipe will mellow it out. I don't know if that will be enough or if I will need to swap mufflers also.

[charliemccraney]

When I installed an H on the milder build of my Y, it did make it slightly quieter. If it's loud now, it's still going to be loud with the H.
I've heard from reliable sources, friends who race superstock and pure stock, that an X is the way to go. I doubt it will make it any quieter, though. I run an X right now.

[BlueGhost]

Chad. In the old days we used to shoot some spray paint on the exhaust pipes in the general area of the transmission, drove the truck or car and then looked for the "hot spot" where the paint burned off, and then located the H-pipe in that area.
See you and Hector at Pate.
U@ss

That's the method I've always head, and plan to use. Trying to get this thing quieted down a little bit, I may swap my chambered mufflers for the round magnaflows. If I swap mufflers and the H-pipe I'll get an exhaust shop to do it and have flanges welded in where I can drop the H-pipe out between the headers and mufflers to get to the transmission. If I just do the H-pipe I will try it myself.

I'm planning to change up the exhaust a little, and get some tunes in it and drive it Pate this year.

[Uncle Skip]

Chad, where did you buy your H-pipe.
I need one too.
S

[jwh f-100]

I have a H-pipe.

I installed it mainly because my exhaust exits infront of the rear wheels (one each side) and I did not want to hear just half of the engine when just the drivers window is down. When I got my truck it had stacks on it and with just the drivers window down it sounded to me like a farm tractor ..

To add the H I just drilled, with a hole saw, a 2 1/4" hole in to my 2 1/2" pipes then used a 2 1/4" cross pipe..

[montego69]

Guys,

When my old turbo mufflers rusted out, I added louder mufflers and a universal x pipe kit from pypes. (www.pypesexhaust.com) The sound in the cabin was about the same afterwards. I think the flow through an X must tone some of the loudness out by bringing the pulses together. Plus the flow through the exhaust system is much smoother. I picked up some acceleration which I contribute to the free-flowing quality of the exhaust system.

Nick

[BlueGhost]

Chad, where did you buy your H-pipe.
I need one too.
S

Hector originally bought it for the Nova, but when he had the exhaust done the shop just made one instead of using the kit.

I'm sure it came from Summit. I think its a Flowmaster one, you can get the Summit brand one a little cheaper and I'm sure its the same thing. Its made to slip over 2.5 inch pipe, or what ever diameter you buy. It comes with one strait crossover pipe and one with a slight bend in case you need it for clearance.

[BlueGhost]

Guys,

When my old turbo mufflers rusted out, I added louder mufflers and a universal x pipe kit from pypes. (www.pypesexhaust.com) The sound in the cabin was about the same afterwards. I think the flow through an X must tone some of the loudness out by bringing the pulses together. Plus the flow through the exhaust system is much smoother. I picked up some acceleration which I contribute to the free-flowing quality of the exhaust system.

Nick

I've head that x-pipe are better for all out horsepower than an H-pipe. I've also head that the smooth the low rpm sound but make the higher revs sound raspier. Where the H-Pipe still smooths out the sound over strait duals and gives a deeper over all sound.

I'll be going with the H-Pipe because I already have the kit, and with the way my exhaust is run it would take a lot of rework to put in an X-pipe.

[STOFFER]

the H-pipe is a more "traditional" sound


the H-pipe will help in the lower to mid rpms, the X-pipe will help in the mid to higher rpms

[charliemccraney]

I've also head that the smooth the low rpm sound but make the higher revs sound raspier. Where the H-Pipe still smooths out the sound over strait duals and gives a deeper over all sound.

For the x-pipe, think of the sound of a new mustang. Many people think I have a 4.6 because of the way it sounds. When I tell them what it really is they say "a what?"

[Ford blue blood]

Running the tail pipes out the back rather than dumping in front of the rear axle under the truck will go a long ways in reducing the noise in the cab. You are getting a double whammy with the noise being trapped under the truck between the body and the hard tar/pavement.

[BlueGhost]

Running the tail pipes out the back rather than dumping in front of the rear axle under the truck will go a long ways in reducing the noise in the cab. You are getting a double whammy with the noise being trapped under the truck between the body and the hard tar/pavement.

My tailpipes go over the rear axle and exit out the sides of the truck between the rear tires and bumper. So I'm only getting noise reflected back at the truck when I'm passing someone or next to a barrier.

I'm leaning more towards replacing the mufflers when I add the H-pipe. I guess my style of mufflers are more of a resonator than a muffler. They are strait through without any packing. Similar to these



I'm thinking of replacing them with the round magnaflows. They should almost drop in, and will bring the noise down a little, but still be aggressive.

[BlueGhost]

Well, after thinking about it for a bit, I member taking one long drive in the truck after we put the AFR heads on but before we swapped the AOD in. The exhaust didn't seem that loud from inside the cab on that trip, even though it was obviously louder than before the new heads here installed.

I think the AOD may be the offending party in a roundabout way. I'm thinking that it drooped the cruising RPMs just enough to put the exhaust in the dreaded 2K drone area at highway speeds. I'll have to try comparing the noise inside the cab in overdrive verses drive.

If this does turn out to be the case, the H-pipe might be enough to kill the drone without having to change my mufflers.

[Tacho]

Running the tail pipes out the back rather than dumping in front of the rear axle under the truck will go a long ways in reducing the noise in the cab. You are getting a double whammy with the noise being trapped under the truck between the body and the hard tar/pavement.

My current exhaust situation is testimony to what blue blood has described. I have 2" pipes with the H crossover and Porter mufflers.
The exhaust comes out in front of the rear tires with turn down tips.
I love the exterior sound but around 2200K RPM's I get the DRONE ZONE and it gives me a headache. I'm short on insulation in the cab, but I know this is not gong to ultimately cure my buzz. Ive got to run the exhaust past the rear tire or to the bumper. Doing this will redistribute the low standing waves after factoring in adding length, bends and the exit.