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Old 11-18-2010, 04:54 PM   #1
s102000
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Dual Exhaust question

I currently have true dual exhaust on my 69 GMC 350 and I'm planning on installing headers soon and new mufflers / exhaust..My question, if I have the muffler shop install an H pipe, will this help the torque numbers if at all? I'm guessing it wouldn't help a stock 350...

Thanks....
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Old 11-18-2010, 05:12 PM   #2
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Re: Dual Exhaust question

You are correct, on a stock to mild build, not much diff will be noticed. Unless I was chasing a noise problem, I would not spend the extra cash for an H pipe.
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Old 11-18-2010, 07:14 PM   #3
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Post Re: Dual Exhaust question

Quote:
Originally Posted by s102000 View Post
I currently have true dual exhaust on my 69 GMC 350 and I'm planning on installing headers soon and new mufflers / exhaust..My question, if I have the muffler shop install an H pipe, will this help the torque numbers if at all? I'm guessing it wouldn't help a stock 350...

Thanks....
Headers will help scavage your exhaust gases out more efficiently than cast-iron stock exhaust manifolds. All the H-pipe does is equal out the pulses of your exhaust system. Not sure what the benefits are but someone here may chime in on that matter for you.

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You are correct, on a stock to mild build, not much diff will be noticed. Unless I was chasing a noise problem, I would not spend the extra cash for an H pipe.
I have to disagree with you here.

Headers will make any engine breath better by removing of spent exhaust gases with little restrictions. If we are talking long tube then YES more torque if shorties then maybe not so much.
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Old 11-18-2010, 07:21 PM   #4
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Re: Dual Exhaust question

The H-pipe on mine cost an extra $50.00, it sounds way better with than without, Imo.
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Old 11-18-2010, 08:52 PM   #5
s102000
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Re: Dual Exhaust question

Quote:
Originally Posted by Lee H View Post
You are correct, on a stock to mild build, not much diff will be noticed. Unless I was chasing a noise problem, I would not spend the extra cash for an H pipe.
That's what I was thinking to, thanks...
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Old 11-18-2010, 08:56 PM   #6
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Re: Dual Exhaust question

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Originally Posted by C20-67_N_MO View Post
Headers will help scavage your exhaust gases out more efficiently than cast-iron stock exhaust manifolds. All the H-pipe does is equal out the pulses of your exhaust system. Not sure what the benefits are but someone here may chime in on that matter for you.



I have to disagree with you here.

Headers will make any engine breath better by removing of spent exhaust gases with little restrictions. If we are talking long tube then YES more torque if shorties then maybe not so much.
Thanks for the info, helps alot
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Old 11-18-2010, 09:00 PM   #7
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Re: Dual Exhaust question

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Originally Posted by big mike71 View Post
The H-pipe on mine cost an extra $50.00, it sounds way better with than without, Imo.
Interesting, I'll need to find one with the H pipe and compare...Thanks..
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Old 11-18-2010, 09:10 PM   #8
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Re: Dual Exhaust question

The H pipe will help the low/ midrange tork, as well as give your exhaust a nicer sound(also said to improve the mileage somewhat?). It wont make your stocker into a "speedracer", but IMO ,its worth adding(I have ran one on all of my trucks,& feel that its a good addition). crazyAl
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Old 11-19-2010, 12:12 AM   #9
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Re: Dual Exhaust question

I have one on mine that i bought from Summit Racing for less then $30. I don't know about the performance, but it sure sounds good through turbo mufflers and 2 1/2 in pipe.
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Old 11-19-2010, 09:37 AM   #10
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Re: Dual Exhaust question

Everyone has an opinion, so here is what I have experienced. Over the years, I have found that the "H" or even better an "X" Pipe will make a difference in the torque of even a mild enigne. The exhaust flow is evened out and the resulting acceleration is smoother. The principal is to create a vortex to pull the exhaust gases out of the opposite side of the engine, thus making it flow better through the cylinders. The better flow out, the better the flow into the cylinders and the more efficient the engine becomes. I would not install any exhaust components without some form of connection between the two pipes. The cross-over even makes the exhasut note sound better and not so harsh and raspy.
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Old 11-19-2010, 10:01 AM   #11
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Re: Dual Exhaust question

if you do add this I'd go with an x pipe . just have whatever set up you pick made tobe easily removed, as most cross under the tranny.. and if you have to work on it or ddrop it.. it's easier if it's easily removeble some like band clams come like ball and socket
fyi even the lowly stocker gets a few ftlb from these..
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Old 11-20-2010, 07:36 AM   #12
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Re: Dual Exhaust question

Quote:
Originally Posted by piecesparts View Post
Everyone has an opinion, so here is what I have experienced. Over the years, I have found that the "H" or even better an "X" Pipe will make a difference in the torque of even a mild enigne. The exhaust flow is evened out and the resulting acceleration is smoother. The principal is to create a vortex to pull the exhaust gases out of the opposite side of the engine, thus making it flow better through the cylinders. The better flow out, the better the flow into the cylinders and the more efficient the engine becomes. I would not install any exhaust components without some form of connection between the two pipes. The cross-over even makes the exhasut note sound better and not so harsh and raspy.
Solid information!

Quote:
Originally Posted by stich626 View Post
if you do add this I'd go with an x pipe . just have whatever set up you pick made tobe easily removed, as most cross under the tranny.. and if you have to work on it or ddrop it.. it's easier if it's easily removeble some like band clams come like ball and socket
fyi even the lowly stocker gets a few ftlb from these..
Could not agree more with your statement.
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Old 11-20-2010, 01:45 PM   #13
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Re: Dual Exhaust question

This is my personal opinion, I have headers with a true dual exhaust (no X or H) and I love the sound of it when at WOT, talk about raspy, LOVE it. Cruising around town it almost sounds like it has a lumpy cam. I just don't know if the small increase in torque is something I would want to trade for the sound. You can always find power other places. It is all up to your personal preference.
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