AFAIK, a compression tester will let you know how good the rings are, but not really how large the combustion chamber is. I'd suggest that putting #1 piston at TDC/Compression and then filling the combustion chamber with oil would be a way that you could measure the size of the combustion chamber. Use a cheap medicine syringe from the pharmacy -- the kind used to dose cough medicine up to 10cc, drop in the oil through the spark plug hole, and you can determine the size when it comes to the bottom of the spark plug threads.
The volume of the piston travel is known, provided that the engine has not been bored or stroked, as 2954cc/6=492.3cc.
Compression ratio=492.3+x/x:1 where x=the volume of the combustion chamber.
So for everything stock on a 7M-GE, the combustion chamber should be as close to exactly 60cc as makes no odds, and this is about as close as you're likely to be able to measure. For 12:1 compression, the combustion chamber would need to be reduced to 44.76cc.
So with a medicine syringe and a bit of oil, you could determine what the static compression ratio of your motor is to within reasonable tolerances. You'll want to evacuate the oil afterwards, but the medicine syringe should allow you to do that reasonably well, though you might get a bit of oil burned next time you start the car.
The volume of the piston travel is known, provided that the engine has not been bored or stroked, as 2954cc/6=492.3cc.
Compression ratio=492.3+x/x:1 where x=the volume of the combustion chamber.
So for everything stock on a 7M-GE, the combustion chamber should be as close to exactly 60cc as makes no odds, and this is about as close as you're likely to be able to measure. For 12:1 compression, the combustion chamber would need to be reduced to 44.76cc.
So with a medicine syringe and a bit of oil, you could determine what the static compression ratio of your motor is to within reasonable tolerances. You'll want to evacuate the oil afterwards, but the medicine syringe should allow you to do that reasonably well, though you might get a bit of oil burned next time you start the car.
