Speedpro H405 pistons, what to expect for performance?

The compression height on them kinda sucks balls. It is 1.637. So they are gonna sit in the hole a good bit. You can overcome that with milling the heads or block or runnin small chamber heads. I believe also too that, even though they are hypereutectic, that they do not require the special top ring gap that the KB pistons do. That might be worth a call to maybe the Summit tech department, but I am almost 100% certain about that.