What does 4-2-1 mean for a header?

This might be a stupid question for some of you, but I'm not real familiar with the 'header' area. What does the 4-2-1 mean?

the header goes from the exhaust ports, in 4 of course, then the pipes merge in to two pipes, then finally into one pipe befire they eventually reach the cat
a 4-1 header just removes the 2, the four pipes merge into one.

correct me if im wrong
4-1 = high end power?
4-2-1 = low end power?

yep :iagree:

Ok, so which one would be the best choice, or is it just depending on which one you want?

if ur spending a lot of time in ur lower rpms, which u prolly are for daily driving, go with the 4-2-1, unless ur planning on autox'ing a lot

always wanted to ask this but was just waiting for the thread to come up...for daily driving and occasional track driving a 4-2-1 header would be best on my B16 because of the lack of torque...right?

always wanted to ask this but was just waiting for the thread to come up...for daily driving and occasional track driving a 4-2-1 header would be best on my B16 because of the lack of torque...right?

I'm pretty sure you are correct there. Almost everyone I know has a 4-2-1 header, and they just drive around / race on occasion.

Yes a 4-2-1 design enphasizes low and mid-range power and torque, while a 4-1 is meant for high end power and torque - they are mostly used for drag cars, if you put them on a D or B you lose that little bit of low end torgue you have 4-2-1 is the way to go