Best 273 and 318 builds (NO 360's please)
My recipe is the same basic idea as any other engine size. Get pistons that yield a decent true compression ratio. Have the lower end blueprinted to make sure you have things right. Give it a set of heads to move enough air for the power level you want. Stick a cam in that will encourage you to drive it rather than hurting the enjoyment. The difference comes in parts costs. you can get 318 pistons cheap that will do a decent job. You cant get 273 pistons IMO without going custom forged.