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-   -   Let's see some H-Pipe Exhausts (https://67-72chevytrucks.com/vboard/showthread.php?t=117946)

68-Mike 08-31-2004 10:39 PM

Let's see some H-Pipe Exhausts
 
Hey guys,

Looking to install a new exhaust with an H-pipe and also looking for header design that won't hang the collector below the frame rails.

I'd be interested in seeing some pics of ya'lls H-pipe routing and looking for any recommendations on headers that don't hang so low.

Thx.
Mike

68w/sbc406 09-01-2004 12:20 AM

my headers hang below the frame rails but i can take pictures tomorrow of the 'H' pipe tomorrow (when its a little lighter outside) if you would like.

68-Mike 09-01-2004 10:08 PM

H-pipe
 
Post pics if you can. I'd be interested in seeing the routing.

Thx.
MIke

68w/sbc406 09-01-2004 11:15 PM

4 Attachment(s)
hope these help

whitesswj 09-01-2004 11:27 PM

question: what is the advantage of getting the h-pipe?
sswj

68w/sbc406 09-01-2004 11:30 PM

it evens the exhaust pressure, you can hear the difference when you stand behind it. the 'blubs' come pretty close to the same time instead of irraticly

RODSBYT 09-02-2004 06:34 PM

Check out shorty headers form early classic enterprises
they fit great and they are ceramic coated with a 2 1/2" collector.
they are made by sandersen. you dont even have to run header gaskets just ultra black permatex. I am going to route my exhaust thru the crossmember
where the trailing arms connect and over the trans cross member so you wont see any exhaust pipes from a side profile. good luck.

Bearhawg 12-13-2022 09:37 AM

Re: Let's see some H-Pipe Exhausts
 
Resurrecting an old thread rather than start a new one. Where did you place your H-Pipe? Picks would be great. Mine is going on a '70 swb C10 and I'm not sure of the best placement without any major modifications. I'm using a stock manifold back 2.25in Heartthrob true dual kit and their H-pipe kit for the same setup. The shop I'm working with is talking about moving the cross member and cutting a passthrough there as well. I have a two-piece drive shaft with a th350. I don't know if it is the long or short tail housing.

This is the kit I'm using. http://www.heartthrobexhaust.com/4143skp.html

Any advice or picks would be awesome!. Thanks!!

Sheepdip 12-13-2022 09:50 AM

Re: Let's see some H-Pipe Exhausts
 
Quote:

Originally Posted by whitesswj (Post 941147)
question: what is the advantage of getting the h-pipe?
sswj

Here's a cut and paste from Nasty Z-28

It's a proven fact that joining the exhaust pipes of multi-cylinder engines improves power and torque over a broad rpm range. A "tuned" set of exhaust headers (with pipes of calculated diameter and length) actually assists sequential firing cylinders to scavenge spent exhaust gases, making room in the cylinder for an undiluted, fresh charge of fuel and air. The velocity of exhaust gases in one header tube causes a low-pressure area in an adjacent tube, literally sucking the exhaust out of that cylinder. The more cylinders, the greater the effect. The late and great Smokey Yunick built several eight-into-one header collector systems that showed increased power on the dyno. Unfortunately, such a system is virtually impossible to package on a typical sedan type of vehicle.

Early H-Pipes
That which works with headers also works downstream with dual-exhaust systems. Unconnected dual exhausts on V-8-powered vehicles act as two independent four-cylinder engines and exhaust systems—and we all know what four-cylinder engines sound like. Back in the '60s, performance engineers at the Big Three car companies discovered that running a balance tube between the two branches of the exhaust system (subsequently called an H-pipe) would broaden the torque curve as well as cut down the interior noise caused by resonance in the exhaust system.

Fast-forward 30 years to the '90s, where a revolutionary development in exhaust technology has taken the balance-tube H-pipe to the next level. Instead of connecting the branches of a dual-exhaust system with a restrictive 90-degree connection, the X-pipe union simply flows the two branches together without changing the direction of exhaust flow, and one side can easily draw from the other for a sizeable reduction in back pressure.

Many companies are now producing X-pipes for most popular performance cars. They are typically available in off-road versions (without catalytic converters) or as 50-state legal models with proper emissions equipment. Most are designed as simple bolt-ons that require less than an hour to install with basic hand tools.

For those who have vehicles where no X-pipe is available, a custom X-pipe can be made by any competent muffler shop by purchasing the X-pipe union and bending up some exhaust tubing to make it fit. If you are fabricating your own X-pipe, a tip is to place the X-pipe union as far to the rear of the car as physically possible—it will make more power that way.

More HP
What can you expect from this modification? A major performance-car magazine did a test on a 350 small-block Chevy engine and the results were fairly spectacular. Torque at 3,000 rpm jumped by 20 lb.-ft. and horsepower increased by 13. These are increases in the useable part of the rpm range and should not only result in quicker acceleration but better fuel economy as well.

What we haven't commented on is the sound. Connecting the branches of the dual exhaust in this manner makes for the sweetest-sounding V-8 you can imagine. Instead of hearing the firing impulses of two disconnected four-cylinder engines, you hear all eight cylinders out of each pipe. What a difference

Bearhawg 12-13-2022 10:26 AM

Re: Let's see some H-Pipe Exhausts
 
Thanks, that’s good info.

I’ve already bought the kit and committed to the H-pipe vs going with the X. The debate over benefits of one over the other has been beaten like a rented mule. I’m trying to figure out where to place the crossover relative to the crossmember and transmission.

Jason Banks 12-13-2022 10:35 AM

Re: Let's see some H-Pipe Exhausts
 
Since my exhaust is tucked up inside the frame, the only real choice I had was between the trans crossmember and the trailing arm crossmember, beneath the trans yoke.

http://67-72chevytrucks.com/gallery/...ust-resize.jpg

http://67-72chevytrucks.com/gallery/...5_15_20_43.jpg

Bearhawg 12-13-2022 11:02 AM

Perfect! Thanks!

1971Stepside 12-13-2022 11:17 AM

Re: Let's see some H-Pipe Exhausts
 
1 Attachment(s)
Here is my set up on an LS. Using Speed Engineering long tubes with Hooker Blackheart exhaust system.

custom10nut 12-14-2022 12:26 PM

Re: Let's see some H-Pipe Exhausts
 
1 Attachment(s)
Good information in this thread.
I fabricated an H-pipe similar to the ones in these pictures.

Who makes the clamps shown in the picture?
Are they stainless steel? (I don’t have a SS system”
I’m interested in these, because I would like the ability to unhook the exhaust, if I ever need to work on the transmission.

Accelo 12-14-2022 01:12 PM

Re: Let's see some H-Pipe Exhausts
 
Here is a link to Summit clamps.
https://www.summitracing.com/parts/sum-694250

My exhaust guy only uses the three bolt up clamps. I Told him the only requirement was to be able to remove the transmission. Now I have a new converter to install. Guess what? I can't get it out without cutting the exhaust. I should have referred to him as my former exhaust guy.

Jason Banks 12-14-2022 03:22 PM

Re: Let's see some H-Pipe Exhausts
 
Accello didn't even link the most expensive ones possible, but I used cheap ebay ones - https://www.ebay.com/itm/302947945735

Those are 3 inch but I used 2 1/2

RichardJ 12-14-2022 05:07 PM

Re: Let's see some H-Pipe Exhausts
 
1 Attachment(s)
I've always used 2-bolt flanges for a crossover. Even though I don't need to remove the exhaust in order to get to the trans on my inline six, I wanted to be able to handle one side at a time if I ever had to remove it. The long tube header collectors are staggered about 6", so i staggered the crossover, the same distance. The curved tubes on the crossover worked perfectly for the stagger.
The V-bands are nice and modern, but the 2-bolt flanges have always worked well and not leaked for me on a crossover.

sfont66 12-14-2022 09:29 PM

Re: Let's see some H-Pipe Exhausts
 
2 Attachment(s)
I have the Speed Engineering long tubes on a Ls swapped 72 C10. At the time I was short on cash, and trying to get my project back together. I threw together a cheap exhaust using mostly used pipe I had laying around. Out of the headers it’s 3” , then changes to 2.5” at the H pipe, then it runs through the trailing arm crossmember and out the side in front of the back tires.
I did buy the v band clamps but chose to save them for when I do a nicer exhaust, ( I hope to make it all 3” soon)
Like others have done I used the butt style SS clamps from Summit racing. The butt style are quick and easy to work with, and have been working well for more than 1200 miles this past summer.


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