I took a lot of advices from Georges because I am not a motorist but I was an engineer and his explanations seem to me all to be coherent from a technical point of view.
So, 383 CI rather than 393 to have a shorter stroke, therefore a smaller rod angle and therefore less stress on the walls of the cylinders which are THE weak point of the Cleveland blocks.
RossPiston pistons, always following George's advice, except that the custom pistons that Rosspiston delivered to me don't have the full circular skirt !!!
I contacted them and they told me that even in the case of full skirts, the pistons being very slightly oval, the skirt does not press on the cylinders walls and the pressure is not reduced. George's explanation would therefore not be good according to the brand he recommends ??? I admit that I don't know who to believe, even if Rosspiston's argument seems valid to me.
No camshaft with reduced base circle because the crankshaft outside diameter is roughly the same as the original; the stroke is increased by reducing the diameter of the big side of the connecting rod, 2.10'' instead of 2.31'' for the original ones (Chevy SB rods)