Tech / Misc Tech topics that don't seem to go elsewhere.
Sponsored by:
Sponsored by:

Why headers are important for extra hp.

Thread Tools
 
Search this Thread
 
Old Nov 11, 2009 | 12:19 PM
  #1  
Janet@bisimoto's Avatar
Thread Starter
 
Joined: Aug 2009
Posts: 1,504
Likes: 0
Default Why headers are important for extra hp.

The header can produce substantial amounts of power on a motor with very few negative compromises. They are a rare, win-win mod, with hardly any trade offs.

Heads make more power by primarily using resonance tuning to create a low pressure, reflected wave, rarefaction (vacuum) pulse during the overlap period. The overlap period is in between the end of the exhaust stroke and the beginning of the intake stroke, where both the intake and exhaust valves are open at the same time for a few degrees of crank rotation.

On a header each individual exhaust port is treated to is own separate primary runner instead of merely dumping into the shared main pipe fo a log manifold. That is why is it better to use a real tubular header over a cast iron Honda manifold.
Reply
Old Nov 11, 2009 | 05:38 PM
  #2  
DCFIVER's Avatar
Honda-Tech Member
Community Builder
Liked
Loved
Community Favorite
 
Joined: Mar 2004
Posts: 4,796
Likes: 37
From: Looking for SloMofo....
Default Re: Why headers are important for extra hp.

Originally Posted by robert@bisimoto
The header can produce substantial amounts of power on a motor with very few negative compromises. They are a rare, win-win mod, with hardly any trade offs.

Heads make more power by primarily using resonance tuning to create a low pressure, reflected wave, rarefaction (vacuum) pulse during the overlap period. The overlap period is in between the end of the exhaust stroke and the beginning of the intake stroke, where both the intake and exhaust valves are open at the same time for a few degrees of crank rotation.

On a header each individual exhaust port is treated to is own separate primary runner instead of merely dumping into the shared main pipe fo a log manifold. That is why is it better to use a real tubular header over a cast iron Honda manifold.
Nice. Trade offs include increase NVH in some chassis and for some this is unacceptable.
Reply
Old Nov 12, 2009 | 11:13 PM
  #3  
fourthgenhatchB17's Avatar
Honda-Tech Member
 
Joined: Apr 2003
Posts: 5,365
Likes: 2
From: 60ft garage, CA, USA
Default Re: Why headers are important for extra hp.

Originally Posted by DCFIVER
Nice. Trade offs include increase NVH in some chassis and for some this is unacceptable.
And dont forget about cost $$, complexity, and space constraints.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Rinsta
Honda Prelude
1
Jun 24, 2009 01:48 PM
shinji666
Acura Integra
1
Oct 10, 2004 07:03 AM
CIVIX
Honda Civic / Del Sol (1992 - 2000)
5
Apr 23, 2004 05:56 AM
T3
Drag Racing
10
Feb 26, 2003 05:34 PM
sslude
Tech / Misc
5
Feb 19, 2003 09:12 AM




All times are GMT -8. The time now is 04:12 AM.