273/318 Heads

Practice on junk. Go to pick n pull salvage yard get junque to port if you want to practice. Closed chamber refers to the size of the combustion chamber where the valve faces are. Closed chamber means small combustion chamber space it this area where open chamber this area if Yuuuuge and equates to low compression. Circled part is "the chamber". Open chamber refers to this part of the head having a lot of CCs of volume.

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