Headers: What's the difference?

[imported_TunerX]

Can somebody please explain to me the purpose and the benefits of all the different header configurations, for example what's the benefit of a 4-2-1 header over a 4-1 header. I never understood that.

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[option2]

A 4-2-1 is designed to keep some of the low end torque that you'll lose with a 4-1 design. A 4-1 is made for top end gains where your not so concerned with lowwerend torque. Another good thing to takin into account is the size of the primaries.

[anteater]

I disagree with option2.
4-1 is designed for more low end power.

Shorter tube headers will give you more low end power, and reduce top end power.
Longer tube headers will give you more top end power, and reduce low end power.

This means that 4-1 is going to give you more low end power and less up top than a 4-2-1.

[imported_TunerX]

Originally Posted by anteater

I disagree with option2.
4-1 is designed for more low end power.

Shorter tube headers will give you more low end power, and reduce top end power.
Longer tube headers will give you more top end power, and reduce low end power.

This means that 4-1 is going to give you more low end power and less up top than a 4-2-1.

What do you mean shorter tube? are you talkin about the length of the header piping itself?

[Darth]

I'd say so. By splitting into more, 4-2-1 has "longer" tube space compared to 4-1.

[option2]

Look up some dyno graphs of header comparisons, every one ive seen the 4-1 has more topend and less torque then the 4-2-1 designs.

[imported_TunerX]

Originally Posted by option2

Look up some dyno graphs of header comparisons, every one ive seen the 4-1 has more topend and less torque then the 4-2-1 designs.

I know the basics on engines. What are the primaries?

[imported_Tricky]

Im out on this argument until i see some proof or opinion from an experienced mechanic!

Surely there is a website out there that explains the differences?

[option2]

Im not trying to argue, its just from the dynographs for the 2.5 liter qr25de motor in my specV every 4-1 header has more up top then the 4-2-1 designs. Primaries are the first four tubes that come right off the head. The bigger they are the the better they flow obviously, to big is bad though cause you'll lose a ton of backpressure. If honda motors see beter results with a 4-2-1 header then more power to you, but every fast honda around here has a 4-1, that doesnt mean **** though. Ill try to find some dynographs later today after i get off work

[anteater]

Perhaps its different for different cars then.
Some cars react better to 4-1 and some to 4-2-1.