The Apfelbeck Project (Serious T4 engineering)

[cnavarro]

If you have them cast, why not use alusil and then have the pistons cast-iron plated? As far as flame ringing, there are a multitude of aftermarket designs where the cylinder and head have a ring groove machined into both and the ring actual interfaces with both surfaces. Some are an actual groove whereas other are a ledge (which leaves the top surface thicker at the failure point).