12ST Head Chamber Volume

[Peredur]

I'm thinking of building an experimental 12ST and want to get the maths sorted to see if she'll fly, so:

Has anyone here measured the chamber of a 12ST head? What was the volume?

I would measure it myself but I'm yet to pick the engine up.

Thanks in advance

[Peredur]

Anyone?

[therealnovaboy]

Theoretically, Combustion chamber volume = swept chamber volume/(comp ratio-1)

What is it your doing. It's probably been talked about on here and never done a hundred times before.

[Peredur]

Thank but I'm looking for a measurement of the volume of the head chamber not the whole chamber.

What I'm thinking of doing is a long stroke 1200 with flat top pistons but I need to know the volume of the head to get the maths down first to see if the idea will fly.

[mowgli]

its about 33cc iirc.. but I haven't looked at a 12st head for a very long time

[Peredur]

Thanks mowgli! I'll cc the head once i get the engine and strip it down.

[winchesterpaul]

i've just picked up a 1.2 st engine for my autograss car, got twin choke inlet (1.3 ?) and going to use a 4 branch. its all supposed to be kept fairly standard. i think a 1.3 cam will fit ? and i read somewhere skim a bit off the cam box ?? if so how much ??