Headers
been there done that
Joined: Jun 2002
Posts: 30,637
Likes: 0
From: 916
Originally Posted by lilgrasshopper
Here's what came out of the article on the 4-2-1 vs 4-1:
CONCLUSION ABOUT HEADER DESIGN
So the old adage that 4-1 = more peak hp with a loss in midrange torque and 4-2-1 = more midrange torque with less peak hp is an obsolete idea.
Newer hybrid headers of the 21st century are a fusion of the old 4-1's extra length with the 4-2-1 layout, have stepped diameters, and have large diameter collectors. So you have low end peak torque with enough breathing capacity to support more peak gains (the best of both worlds).
CONCLUSION ABOUT HEADER DESIGN
So the old adage that 4-1 = more peak hp with a loss in midrange torque and 4-2-1 = more midrange torque with less peak hp is an obsolete idea.
Newer hybrid headers of the 21st century are a fusion of the old 4-1's extra length with the 4-2-1 layout, have stepped diameters, and have large diameter collectors. So you have low end peak torque with enough breathing capacity to support more peak gains (the best of both worlds).
CHRISTMASTIME IN IRAQ
Joined: Apr 2003
Posts: 12,413
Likes: 0
From: Bay Area
Originally Posted by lilgrasshopper
Here's what came out of the article on the 4-2-1 vs 4-1:
CONCLUSION ABOUT HEADER DESIGN
So the old adage that 4-1 = more peak hp with a loss in midrange torque and 4-2-1 = more midrange torque with less peak hp is an obsolete idea.
Newer hybrid headers of the 21st century are a fusion of the old 4-1's extra length with the 4-2-1 layout, have stepped diameters, and have large diameter collectors. So you have low end peak torque with enough breathing capacity to support more peak gains (the best of both worlds).
CONCLUSION ABOUT HEADER DESIGN
So the old adage that 4-1 = more peak hp with a loss in midrange torque and 4-2-1 = more midrange torque with less peak hp is an obsolete idea.
Newer hybrid headers of the 21st century are a fusion of the old 4-1's extra length with the 4-2-1 layout, have stepped diameters, and have large diameter collectors. So you have low end peak torque with enough breathing capacity to support more peak gains (the best of both worlds).
FuK JDM
Joined: Jul 2004
Posts: 2,493
Likes: 0
From: The Left Lane, CT
i have a dc 4-2-1 header and it works fine...im not sure about the whole 10-12 hp gain but it deff makes a little difference. then again its not like im at the track ever...its just my everyday driver
