The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 04-29-2011, 07:52 PM   #1
Stricklinator
Registered User
 
Stricklinator's Avatar
 
Join Date: Feb 2011
Location: Murrieta, California
Posts: 234
Straight dual or H-pipe exhaust?

I replaced the rusted out exhaust on my 1969 C/20 with a straight dual exhaust kit from LMC (poor fit by the way, the shop had to re-bend almost everything). The shop says that they will add an h-pipe for $50. My question is whether or not I should add an h-pipe and whether $50 seems fair? I have a stock 307 with a 4-speed. Thanks
Posted via Mobile Device
__________________
1969 C/20, 307, 4-speed, rusty with manual steering and brakes!
Stricklinator is offline   Reply With Quote
Old 04-29-2011, 08:08 PM   #2
lsteiner72
Registered User
 
Join Date: Jan 2011
Location: Waukesha,WI
Posts: 25
Re: Straight dual or H-pipe exhaust?

IMO yes H pipe is worth it and worth the $50. a x pipe would be even better but probably really hard to do with the pre made exhaust system.
lsteiner72 is offline   Reply With Quote
Old 04-29-2011, 08:23 PM   #3
LONG 2B LOW
Registered User
 
LONG 2B LOW's Avatar
 
Join Date: Apr 2011
Location: Phoenix AZ
Posts: 15
Re: Straight dual or H-pipe exhaust?

Any cross over pipe in your exhaust is always a benefit, an x pipe would definitely flow better but an h pipe will equal out the pressures in the exhaust just the same, I run an h Pipe on my 72 c20 and my 69 camaro and suggest/recommend a cross over pipe of some sort to anybody, and yes 50 dollars sounds reasonable, I'd do it
Posted via Mobile Device
LONG 2B LOW is offline   Reply With Quote
Old 04-29-2011, 08:24 PM   #4
Mike Bradbury
Registered User
 
Mike Bradbury's Avatar
 
Join Date: Apr 2008
Location: San Diego California
Posts: 1,316
Re: Straight dual or H-pipe exhaust?

I have never seen the data between the X and H set up. The theory is the exhaust gasses from one side will help vacuum the other side. With an H pipe it seems that it would balance the sound of a dual exhaust but it might not benefit performance nearly as much as an X pipe because the exhaust gases are now trying to travel both ways in the H pipe actually slowing the flow down. Would love to see some dyno test data on the two systems.
Posted via Mobile Device
__________________
I'd rather attempt something great and fail.. than try something ordinary and succeed. Norman Vincent Peale

Project: Barn Raising http://67-72chevytrucks.com/vboard/s...d.php?t=414961

Project: 30 Be Low https://67-72chevytrucks.com/vboard/...d.php?t=830583

Last edited by Mike Bradbury; 04-29-2011 at 08:27 PM.
Mike Bradbury is offline   Reply With Quote
Old 04-29-2011, 08:26 PM   #5
RichardJ
Registered User
 
Join Date: Apr 2010
Location: So Cal
Posts: 1,420
Re: Straight dual or H-pipe exhaust?

Tell them for the $50 you want two-bolt flanges so you can separate and remove the sides individually. Have them locate the flanges to one side of the crossover, so you can remove only the long side if you have to drop the trans.
__________________
'67 GMC 2500, 292, 4spd, AC
RichardJ is offline   Reply With Quote
Old 04-29-2011, 09:36 PM   #6
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
Re: Straight dual or H-pipe exhaust?

with a stock 307?
I say you'll never see an improvement, and it is probably pretty quiet already so noise isn't a factor...
spend the 50 on gas
Longhorn Man is offline   Reply With Quote
Old 04-29-2011, 09:38 PM   #7
leddzepp
Moderator
 
leddzepp's Avatar
 
Join Date: May 2007
Location: Southern Cal
Posts: 19,995
Re: Straight dual or H-pipe exhaust?

Quote:
Originally Posted by Longhorn Man View Post
with a stock 307?
I say you'll never see an improvement, and it is probably pretty quiet already so noise isn't a factor...
spend the 50 on gas
Agree 100%
__________________
1972 C/10 Cheyenne Super SWB. Restored, loaded, slammed.

1968 C/10 50th Anniversary LWB. Unrestored, stock, daily driver/work truck.


RIP ElJay
RIP 67ChevyRedneck
RIP Grumpy Old Man
leddzepp is offline   Reply With Quote
Old 04-29-2011, 10:10 PM   #8
lakeroadster
Account Suspended
 
Join Date: Sep 2009
Location: High Plains of Colorado
Posts: 2,485
Re: Straight dual or H-pipe exhaust?

Quote:
Originally Posted by Longhorn Man View Post
with a stock 307?
I say you'll never see an improvement, and it is probably pretty quiet already so noise isn't a factor...
spend the 50 on gas
x3!

I have true duals on my 350, I prefer them over the sound of an "x" or "h" pipe set-up.
lakeroadster is offline   Reply With Quote
Old 04-29-2011, 10:46 PM   #9
big_al_71
Registered User
 
big_al_71's Avatar
 
Join Date: Jun 2008
Location: South Florida
Posts: 11,375
Re: Straight dual or H-pipe exhaust?

I dont have either I went with straight duals....
__________________
Get your facts first, and then you can distort them as much as you please!!!!!.



Sylvester's build thread >>>http://67-72chevytrucks.com/vboard/s...ht=big+rebuild
big_al_71 is offline   Reply With Quote
Old 04-29-2011, 10:55 PM   #10
OJ1988
Just a car guy
 
OJ1988's Avatar
 
Join Date: Feb 2006
Location: New Washington, IN
Posts: 991
Re: Straight dual or H-pipe exhaust?

Ime the h pipe helps get rid of the pop and cackle sound ESP on deceleration.
I bought a jegs h pipe kit.
Posted via Mobile Device
__________________
1955 belair Blown Pro Street cruiser
1971 Camaro Pro Touring
1973 Vega Drag Car
1970 C20 tow rig
OJ1988 is offline   Reply With Quote
Old 04-29-2011, 10:57 PM   #11
OJ1988
Just a car guy
 
OJ1988's Avatar
 
Join Date: Feb 2006
Location: New Washington, IN
Posts: 991
Re: Straight dual or H-pipe exhaust?

I remember one of the mustang rags dis a shoot out on a mild 5.0
both saw improvements.
The h pipe made more of a low end difference and the x improved the numbers up top.
Neither made big gains.
Posted via Mobile Device
__________________
1955 belair Blown Pro Street cruiser
1971 Camaro Pro Touring
1973 Vega Drag Car
1970 C20 tow rig
OJ1988 is offline   Reply With Quote
Old 04-29-2011, 11:35 PM   #12
stich626
Account Suspended
 
Join Date: Sep 2010
Location: hingham ma
Posts: 1,721
Re: Straight dual or H-pipe exhaust?

you didn't say what size the pipe is 2.25 or 2.50"
but the h pipe will only hurt power in that 307.. and not worth it.. unless the 307 is a stop gap to something better..
total waste in a basicly stock low compression engine that never see's north of 4000rpm
save your 50 bucks,,
stich626 is offline   Reply With Quote
Old 04-30-2011, 09:01 AM   #13
Hart_Rod
*************
 
Hart_Rod's Avatar
 
Join Date: Apr 2005
Location: Pensacola, FL
Posts: 17,837
Re: Straight dual or H-pipe exhaust?

Quote:
Originally Posted by big_al_71 View Post
I dont have either I went with straight duals....
Me too! And I love the sound.....

Hart_Rod is offline   Reply With Quote
Old 04-30-2011, 04:33 PM   #14
Stricklinator
Registered User
 
Stricklinator's Avatar
 
Join Date: Feb 2011
Location: Murrieta, California
Posts: 234
Re: Straight dual or H-pipe exhaust?

Thanks for the feedback everyone. I decided not to add the h-pipe as long as I have the stock 307. I figure going from a single 2" to dual 2.25" with that engine is probably overkill already.
Posted via Mobile Device
__________________
1969 C/20, 307, 4-speed, rusty with manual steering and brakes!
Stricklinator is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:23 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com