head differences

[ScottyCBoy <ScottyCBoy@aol.com>]

I've got a question..

Whats'  the differences /gains losses, advantages between the open combustion
chamber ( 1978-1984 5000s, 5000turbos) and the closed chamber head, ( 84 up
4000, 85 up 5000, 80/90 NG)  Audi used the closed chamber heads when they
upped the compression ratio.  I know closed chamber heads offer more knock
protection, by having a shorter flame path, and are more fuel efficient.  Any
help will be greatly appreciated...

Scott