Header Gasket Choice

[TucsonHooligan]

I got a set of headers and they came with a gasket that matches the size of the ports on the headers themselves, which are a couple inches square on all 6. I have a Fel-Pro gasket set I bought to rebuild the motor and it came with an exhaust gasket as well, but it matches the ports on the head, meaning the 2 center cutouts on the gasket are bigger than the other 4. Which one is better to use? Does my description make sense?

 

[thesameguy]

In general the gasket wants to match the larger of the two surfaces, so if the ports on the header are bigger, use it's gasket. You don't want hot exhaust or hot liquid or whatever hitting an exposed gasket surface.

 

[JackFish]

Yah header gaskets are different than the stock ones as far as I know.
The stock ones would be shaped for the siamesed 3 and 4 exhaust port.

http://www.classicinlines.com/proddetai ... HEG&cat=81

 

[TucsonHooligan]

Why the hell would they make a gasket like the one in that picture? Even without aftermarket headers, it's still too big to match a stock head. Doesn't make sense. And what about cutting the center section of the gasket on the middle port, making it one big hole as opposed to 2? I don't have a port divider, and am gonna just chamfer the one on the headers for better flow.