Anyone NOT using an H or X pipe? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 03-16-2012, 09:19 PM
Registered User
 
Last photo:
Join Date: Dec 2011
Posts: 23
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Anyone NOT using an H or X pipe?

Installing Dynomax Ultraflow exhaust shortly and need to decide H pipe or no H pipe and I'm leaning strongly toward NO H pipe (forget the X pipe - don't like the sound and I don't care if it has more HP. The H pipe sounds much better and has more torque). It's not about power but sound I'm looking for.

Just installed new stroker motor (in signature block) and without an H pipe it sounds just right - plenty of thumpy idle. The Ultraflows should enhance this; however, I'm concerned if I add an H pipe it will:

1- lose the nice lumpy idle I'm hearing and feeling (I like that);
2- change the tone to something I will not like (understand it is deeper sounding and from ALL the videos I've seen on UTube I'm not totally impressed with the sound);
3- it cost more to install an H pipe

Anyone out there not using the pipe for similar reasons?

==========================
'65 - Pony Interior; Classic Auto A/C; 363ci Stroker 535hp; Dart 4 Bolt main; forged internals with additional machining; Eagle forged steel crankshaft; Steel beam connecting rods; Mahle forged pistons 10.2 to 1 compression; Edelbrock Rollin Thunder Cam; CNC Ported Xtreme RPM Edelbrock heads; Edelbrock Air Gap manifold; Holly 770 Ultra Avenger; balanced & blueprinted. First run video - http://youtu.be/xIRAUFs2NTU

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 03-16-2012, 10:34 PM
bentwings's Avatar
bentwings
 
Last photo:
Join Date: May 2002
Location: St.Paul, Minn
Age: 72
Posts: 1,791
Wiki Edits: 0

Thanks: 0
Thanked 16 Times in 15 Posts
I made my own 3" system including modified heders and do not use X or H or any interconnecting stuff. Sound is fine and not raspy.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 03-16-2012, 11:30 PM
thinwhiteduke's Avatar
Living In The Past
 
Last photo:
Join Date: Dec 2011
Location: Downunder
Age: 54
Posts: 428
Wiki Edits: 0

Thanks: 36
Thanked 36 Times in 32 Posts
I've owned several V8's over the years, mainly pre-1975, and have never ever run any connecting pipes X or H's . I like the (stereo) sound of two separate banks, I never considered ever joining them together.
Does it make more power? I didn't know that....
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 03-17-2012, 02:15 AM
4 Jaw Chuck's Avatar
Hotrodders.com Moderator
 
Last photo:
Join Date: Mar 2002
Location: Manitoba, Canada
Age: 46
Posts: 4,875
Wiki Edits: 0

Thanks: 0
Thanked 71 Times in 59 Posts
Don't believe everything you read in a magazine, if there was a difference between when I tried with and without an "H" connecting pipe I couldn't hear it...never felt a difference on the road either.

Lot a hype around this "performance modification", sells a lot of $1200 exhaust systems for the retailers and mfg's.

BTW 99% of all race vehicles have single exhausts...that makes the most power...end of story...no hype.
__________________
Outlawed tunes from outlawed pipes
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 03-17-2012, 06:24 AM
Member
 
Last photo:
Join Date: Dec 2004
Location: San Antonio, Texas
Age: 50
Posts: 4,021
Wiki Edits: 0

Thanks: 0
Thanked 23 Times in 23 Posts
I have build plenty of exhaust systems without cross over pipes. But ended up putting in a H pipe in most of them after the test drive.

The cross over pipe is to reduce the exhaust drone in the cabin. Not a power thing.


If you like the way your exhaust sounds now (in and out of the car) then don't mess with it.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 03-17-2012, 07:27 AM
Registered User
 
Last photo:
Join Date: Jul 2007
Location: norcal
Age: 58
Posts: 762
Wiki Edits: 0

Thanks: 1
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by 4 Jaw Chuck
Don't believe everything you read in a magazine, if there was a difference between when I tried with and without an "H" connecting pipe I couldn't hear it...never felt a difference on the road either.

Lot a hype around this "performance modification", sells a lot of $1200 exhaust systems for the retailers and mfg's.

BTW 99% of all race vehicles have single exhausts...that makes the most power...end of story...no hype.
true and not true. on my gasser open headers, tuned equal pipes i learned were the way to go.
on my 66 396 back in the 60s i did a lot of experiments, screw the sound, i was looking for power. an H pipe welded in after the the equal lengh headers and before the mufflers did indeed give more power. i oxy acet welded the that H pipe into the dual exhaust system, it was a no cost mod back in the day that worked.
why would anybody spend big bucks on an exaust mod when you can weld up your own, i just don't get it.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 03-17-2012, 09:01 AM
matts37chev's Avatar
I don't understand?
 

Last journal entry: this is only a test
Last photo:
Join Date: Jan 2009
Location: Shelton,Wa.
Age: 45
Posts: 2,420
Wiki Edits: 0

Thanks: 0
Thanked 5 Times in 4 Posts
would change the color of your car just because the magazines and some people on the interweb said they like a different color better?

just run it like it is, if it sounds right to you
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 03-17-2012, 11:04 AM
Registered User
 
Last photo:
Join Date: Dec 2011
Posts: 23
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Here's a short video of the motor running just after installing it. http://youtu.be/6t3CTog58Io . It has stock mufflers and wants to bust out - the exhaust pulse shoots way out the back like I've never seen before - probably b/c it has 2 1/4" pipes and is a little restrictive.

It has solid adjustable motor mounts, so the car really rocks at idle and I like it that way. I'm convinced now I like the true duals - you can watch each bank fire separately and it has that muscle car feel.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 03-17-2012, 11:35 AM
SSedan64's Avatar
Registered User
 
Last photo:
Join Date: Dec 2007
Location: Macon, GA.
Age: 50
Posts: 6,016
Wiki Edits: 0

Thanks: 0
Thanked 46 Times in 46 Posts
I've always like the Individual/Non-crossed Pipe sound.
Some Muffler/Crossover/Tailpipe comparison Info >> http://www.boyleworks.com/ta400/psp/exhaust.html
I don't think they did a with & without X-over test.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 03-17-2012, 11:50 AM
Registered User
 
Last photo:
Join Date: Dec 2011
Posts: 23
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by SSedan64
I don't think they did a with & without X-over test.
I find very interesting myself - how the entire internet is void of studies/comparison of X-over vs. no X-over. Hmmm - maybe this is a bunch of magazine hype to sell products. Any honest study would include the H-pipe vs. X-pipe vs. NO PIPE. After all, what is the base line? (NO PIPE).
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 03-17-2012, 11:53 AM
Registered User
 
Last photo:
Join Date: Dec 2011
Posts: 23
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Oh, and it smooths it out and balances the power - well, how much? Where are the dyno pulls. We know the H has more torque and X more hp (slightly) but where is the "no pipe" in the equation?? Do you think we're idiots! Better not answer that one.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 03-17-2012, 02:19 PM
Valkyrie5.7's Avatar
www.generationhighoutput. com
 
Last wiki edit: Painting chrome wheels
Last journal entry: Stopping my journal entries here
Last photo:
Join Date: Feb 2010
Location: Phoenix
Age: 27
Posts: 897
Wiki Edits: 15

Thanks: 147
Thanked 71 Times in 62 Posts
I like the sound of either honestly. Each has it's own merit, and I think sound is a big part of the overall "theme" of the car so to speak. A muscle car with flowmasters and an x-pipe rubs me just as wrong as a brand new mustang with straight pipes and glass packs.

If you're going for sound, you should follow what you know. An old rod sounds right with straight pipes if that's what the theme demands, or ultimately if it's what you want. As far as the purpose of H and X pipes in an exhaust system, Oldbogie has explained it clearly in quite a few threads similar to this one. These quotes are the first three I found just by searching "Oldbogie H pipe" in our lovely search bar:

From "Why an H pipe ??":

Quote:
Originally Posted by oldbogie
This is one of those places where there's a lot of "Rocket Science" going on.

Basically, it's hard to get pipes and mufflers with enough capacity for a V8 at WOT. 800 CFM carbs or bigger are easy to get while 800 cfm capacity in an exhaust system takes some careful parts selection. Most mufflers, especially cheap ones don't come close (usually about half or less that for a good muffler) so it takes two in order to provide the needed flow capacity.

When duals are tied together, it allows both mufflers to be used by the engine at any given moment, essentially doubling the flow area any cylinder sees. This reduces back pressure which improves fuel efficiency and power. Surprisingly, with no other changes to the engine, a typical mild OEM V8 will pick up a mile or two to the gallon and 5 to 10 hp when duals are installed on a vehicle that's used in a mild cruise operating area of its power band; where you'd think duals wouldn't have an impact on engine performance. Of couse they're even more effective for an engine that works hard like a turck needing lots of throttle opening or a high performance engine spun up to a lot of RPM.

However, one of the problems with duals at slow to moderate speeds is keeping the exhaust velocity up so that it pulls a negative pressure in the cylinder during the cam's overlap phase. This allows for complete blow down in the combustion chamber space which the piston can't positively force evacuation of like it does the cylinder. Also, the resulting negative pressure launches the intake mixture into the cylinder as the intake valve just starts to open.

Here's where you get into some Physics of pipe design. An H pipe is typically close to the front of the system because space permits it to be there. At lower RPMs where the extra area/volume of the the duals isn't needed, the exhaust slug pretty much ignors the crossover pipe, keeping velocity up in the primary pipe into which the slug was exhausted. As RPMs come up, back pressure rises to a point where the exhaust slug will begin to use the H pipe as an additional path to more evacuation area/volume. The flow here becomes fairly turbulent as the H pipe presents nothing but sharp edged, right angle corners, this causes efficiency of the pipe to drop as RPMs get really high. The X pipe's crossover is always located further back because it needs a lot of space and the transmission is in the way up front. But as it turns out for "RS" reasons it needs to be further back so things just work out right thru no fault of our own. The X pipe with its smooth transition presents the total area/volume of both pipes and mufflers from the crossover point back to all the flow all the time. At low and moderate engine speeds any exhaust slug entering here can't escape seeing all the area/volume because of the smooth transition. This requires the head pipe to be longer to provide time where the exhaust flow is speedy in the smaller pipe at low to moderate engine revs so that cylinder blow down is evacuating the combustion chamber and intake is starting properly during the overlap phase of the cam. The upside is that the X transition doesn't develop high speed flow interference the H pipe does because none of the flow is forced to make right angle turns which generate a lot of turbulence resulting in the pipe looking smaller to the flow trying to get thru it. The disadvantage of the X pipe is that space is a premium under the car and the X pipe uses a lot of it.

Both pipes will tend to reduce exhaust noise as sound waves take advantage of twice the pipe and muffler area/volume which dissipates them more effectively. This lets you get away with higher flowing mufflers which tend to be noisier than quieter but lower flowing mufflers.

Bogie
From "X pipe or H pipe":

Quote:
Originally Posted by oldbogie
The idea of both is to share muffler capacity of one side with both sides. Mufflers and cats, which you're probably not using, are the biggest flow limiting devices on the engine. So the crossover lets either bank of cylinders to see the total flow of a dual exhaust. It's not quite that straight forward in actual practice, but better than a single exhaust isolated on each cylinder bank. Each has it's own tone qualities, the H pipe emphasizes the lower rumbling notes, the X pipe favors the higher sharper notes, too a large extent the mufflers will affect either crossover's sound preference. Too the end of using both muffler the crossover needs to be ahead of the muffler or cat.

Clearance to the roadway may dictate which, generally I find that X pipes need to mount lower to clear the transmission or drive-shaft where H pipe can often be tucked up between the bell-housing inspection cover and the transmission, but in either case your specific lay out will determine where there's any space/clearance advantage. Headers compared to cast manifolds, or more specifically their collector, will push the H pipe toward the rear and often down to clear the transmission which will then be as low as an X pipe.

Tuners using the H pipe can search for the optimum location on the collector but this is a pain to do and for a street engine not worth the effort for the very small torque gain. The x pipe does not seem to be sensitive to location in terms of offering small gains in one place over another.

Bogie
From "Do I need to add a Y pipe?":

Quote:
Originally Posted by oldbogie
Using an H or X pipe ahead of the cat converters or mufflers allows each side to see the total flow capability of both cats and mufflers combined (in parallel). This reduces high speed back pressure allowing the engine to generate more power. Converters and mufflers being the most restrictive elements of an exhaust system the sharing of capacities is most beneficial to the engine.

There doesn't seem to be any negatives with these set ups, the X configuration consistently shows a small power and torque improvement over the H pipe, but that comes with a harder sound. The H pipe is a very close second on power and torque with a more mellow, but not necessarily quieter, tone at the tail pipes. this is up to you, for myself I prefer the more mellow 1950's tone of an H pipe and glass-packs.

Bogie
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 03-17-2012, 03:03 PM
LATECH's Avatar
Hotrodders.com Moderator
 

Last journal entry: Motor - vator
Last photo:
Join Date: Jul 2010
Location: Northeast Pennsylvania
Posts: 5,154
Wiki Edits: 0

Thanks: 199
Thanked 249 Times in 231 Posts
I have the 2.5 inch Flowmaster "h" pipe crossover mandrel bend exhaust on my 64 poncho. It has a stock 350 (for the time being) in it and the sound is awesome. I am sure twin pipes W/O an "H" crossover or some sort of crossover would be raspy and gnarly. I had twin pipes on my Old F 150 W/O a crossover and it sounded OK in the truck but was snappy and crackly and whatever outside on the street.
Run a crossover of some type. It DOES make a difference.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 03-17-2012, 05:33 PM
68NovaSS's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Working with chromed bolts
Last journal entry: New to me T-Bucket
Last photo:
Join Date: Sep 2002
Location: Nine Mile Falls, Washington
Posts: 5,214
Wiki Edits: 9

Thanks: 98
Thanked 130 Times in 121 Posts
Quote:
Originally Posted by Valkyrie5.7
These quotes are the first three I found just by searching "Oldbogie H pipe" in our lovely search bar:

From "Why an H pipe ??":



From "X pipe or H pipe":



From "Do I need to add a Y pipe?":
Please read the cut and paste guidelines, it's preferred you post a few lines of the text along with a link to the rest. Thanks
__________________
Boost adds dignity to what would otherwise be a vulgar brawl...

Midnight Sun Street Rod Association
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 03-17-2012, 07:55 PM
Member
 
Last photo:
Join Date: Dec 2004
Location: San Antonio, Texas
Age: 50
Posts: 4,021
Wiki Edits: 0

Thanks: 0
Thanked 23 Times in 23 Posts
I like this link about exhaust testing.

http://www.pontiacstreetperformance....p/exhaust.html
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 2 (0 members and 2 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
X pipe or H pipe 46coppertop Engine 7 11-15-2011 08:51 PM
1/2 pipe to male 1/4 pipe thread for shop Mach1460 Garage - Tools 8 09-27-2011 09:38 AM
Flexible Pipe from Compressor to Solid Pipe? cab Garage - Tools 24 12-03-2007 07:55 PM
what is beater H pipe or X pipe rale Engine 2 05-17-2006 06:38 AM
x-pipe, h-pipe and other exhaust questions smlblcks10 Engine 7 11-25-2003 06:05 AM


All times are GMT -6. The time now is 11:06 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.