Reply to "TRW L2416F Piston Compression Height?"

I don't recall that number ever being posted.

You need to measure it with a feeler gauge with the piston installed in the car, and you are measuring how far down in the hole the piston is.

With the canted reliefs in those pistons I want to say that the number was only an approximation to begin with.

They are always a problem to mill them down when the have the domes because you have to pick a common spot on the piston to measure from and that always leaves a little indecision initially.

If you just replace the dished TRW pistons with the flat top TRW you will be fine with the closed chamber heads (61cc) and pump gas. You just don't want the 47cc aftermarket aluminum heads.

You normally don't need to know exactly what the static cr is. You just need to know the vicinity it is in.

The closed chamber Cleveland head starts to show sensitivity to octane sooner then the 289 head does.

I doubt you could run over 10.5:1 actual with todays pump premium gas and don't waste your time on octane booster unless you are adding lead to the fuel. The other stuff won't work.