My 273 is at the machine shop right now. I bought a nice set of NOS .030 flat top pistons for it, but they ended up being too far in the hole to get proper compression. My buddy that is doing the machine work is a HP engine builder for NASCAR folks and has a lot of connections. He called a company called Race Tech, and they are making me set of custom forged pistons for my motor. The price is barely more than the Egge pistons and we are getting modern ring grooves instead of 60-year-old stuff. Race Tech will build you some pistons to your specs, so if you decide to go that route you will need to have your engine builder/machinist to measure twice and order once...lol.