NONONO! Don't even think about building a no-squish engine. No flat tops allowed!
Sure, thay can be made to work. But a good squish engine will beat a good non-squish engine every time. It's a fact. Quicker combustion allows more compression on the same fuel octane plus less time spent building cylinder pressure ahead of TDC. More compression means a more efficient engine. And what does the cylinder pressure BTDC do? tries to push the piston backwards down the cylinder.

It's called negative work.

The fewer degrees of spark advance the engine needs to make max power, the better. Bigblocks used to need 38 degrees. Modern chambers are doing it at 30. Using a "quench dome" piston will help move the awful B/RB combustion chambers into the present.

R.