this may sound dumb, but i really want an answer to this. what is the difference between headers and the regular exhaust manifolds? both take the exhaust out of the motor. headers are usually longer than standard...is it because you are eliminating the 'choke point' where the exhaust all comes together? also, if the motor turns out horsepower, why is the flow so important. not a mechanic this just always made me wonder.thanks

 

can u run as fast as you can coughingor not breathing correctly same goes for the car
headers allow the motor to breath easier less restrictive

 

First, headers flow better than regular manifolds because of their tubular design, not only are they smoother, but they also dissipate heat better(flow is directly related to heat, physics thing). The longer the tubes on a header are, the more low end torque you can get out of them, because they are more "tuned" to the motor. Think of the tuning this way, if a tube on an organ is longer, it resonates at a lower frequency. For headers, when they resonate, they flow better, so if you have a longer tube that resonates at a lower frequency, it flows better than a shorter header at that rpm.

 

thank you for the info. is there a lot of modification needed to install them on a 305? i.e. changing cat converter, or just buyin some other piping from heads to converter.

 

If you're getting headers, you're going to need to update the Y pipe too. Get one from the manufacture you're ordering headers from, unless you're getting one custom fabricated. Other than the header/Y assembly, you can chop and reweld/clamp any cat back system back in because the Y will run in the stock location after the 2 pipes come together.
(side note, did you mean 350? not 305...)

 

thanks. i meant 305. never know when you might run across something dirt cheap. i have no expectations of putting them on unless a great deal were to come up. rather save up and just get a 350. the car is in ok shape. prolly leave 305 in it till it blows up. this was mainly of interest as i keep reading ref headers. wasn't sure how much hp they put out over stock and as to why I got the answer i was looking for. thanks guys