[nonlucendo]

I was wondering what is the difference between the 4-2-1 Race header offered by Focus Central and the 4-1 Race header offered by Focussport or is there even a difference?

 

[Kicknzx3]

the layout, primary size and design, welds, power curve.

 

[nonlucendo]

then what is the difference between the two in relation to their power curve

 

[fokuzsport]

yeah big difference.. 4-1 is illegal

 

[nonlucendo]

Why is the 4-1 illegal and not the 4-2-1?

 

[myFordPerformance.com]

Any race "offroad" header is illegal since you don't have a catalytic converter...

 

[nonlucendo]

well being illegal or legal is of no issue to me, what i'm wondering is what the actual difference in terms of their performance and for what application each header is best suited

 

[fokuzsport]

Why is the 4-1 illegal and not the 4-2-1?

any 4-1 header is illegal

 

[nonlucendo]

(like i stated earlier i don't care about the legalities) it seems that noone here can answer my original question about the power curve difference...*sigh*

 

[Infra3sv]

four pipes goes into two pipes goes into 1 pipe ; 4-2-1.

 

[Kicknzx3]

4-1 is best for midrange hp and top end hp, and 4-2-1 is better for low end power and tq. but still makes good power throughout the powerband, for a car with bolt ons, i'd choose the 4-2-1

i would have posted this before but forgot about this thread and didn't see it on the active list.

 

[EuroZX3]

the more exhaust flow the more your torque curve moves to lower rpms, shorty headers + cat will give u more mid range power if im not mistaken. if i am Ed u better correct my arse

 

[wrcRS]

4-1 offers good top end, 4-2-1 offers a little more midrange with almost as much top end...The differences are VERY SLIGHT though...

 

[00focus]

So how is the 4-1 illegal if it still uses the cat and 02 sensor???

 

[Kicknzx3]

So how is the 4-1 illegal if it still uses the cat and 02 sensor???

because its moved from the stock location and will fail visual

 

[00focus]

in De they dont do visuals so as long as it passes emissions im straight