Is it possible to heat the windshield and passenger compartment in a car with headers? I wouldn't trust a gas heater but was thinking about stuffing a couple of 12V camping hair dryers in the heater ducts. Would probably only be a few hundred watts but might be enough for comfort in early spring and late fall.

basicly, heat exchangers are headers, but with sheetmetal surrounding them to capture some of the heat

for a /4 motor, the h/e's are not the most efficient design flow wise, but they are more or less "headers" already

aftermarket "headers" for the /4 motors are designed to weigh less and flow better.....add some ducting in a similar fashion and you have heat!!!!!!

soem people have had success with electric heaters, do a search here, it's been brought up a gazillion time with what works and does not work and the +/-'s of them

So, light guage steel in the form of a box with ducting and the blower moter could get it done?

KT

It was always my understanding that headers were an option for manifolds, and manifolds were cast. Is this true? Or am I oversimplifying?

that is how I interpret it.....one single piece with multiple inlets/outlets is a manifold

if you have seen the exhaust on a '75/76 1.8 or 2.0, I consider those to be exhaust manifolds that bolt to the head, those in turn are bolted to heat exchangers, but they are not headers....for a '74 and older car, the exhaust consists of a single pipes that converge at the muffler assembly....I really wouldn't consider them "headers" since their secondary function is to help provide heat...but they are a form of a modified header

by "captureing" hot air surrounding the the tube(s), you have made a heat exchanger

confused now?? hahahhaa

Gas heaters get a bad wrap. <_<

This link goes to my Tangerine Super Header page.
about 3/4 down to the bottom you will find the heat exchanger section.
So, to answer your question, yes it is possible to heat the windshield and passenger compartment in a car with headers.

I don't think there's anything wrong with gas heaters, but it would be hard to find a suitable installation location in a 914.