SM Head Modifications on a budget
My RPMs are actually pretty old. I think I originally purchased them back in 2010. I haven't run them for any appreciable time. They've been on the shelf in other words.
Maybe the newer castings are just awful? I've disassembled these heads and there weren't any bad ridges in the bowls at all. I was fairly impressed actually, with the overall quality of the port. Smooth transitions etc. same for the pushrod pinch area. It's all pretty nice actually.
I'm not entirely sure what if anything I'm going to do to these before I put them on the 418. I do know they're going to hold that engine back but I haven't the spare cash to get them ported to the required level. I've thought about tubing the head bolt holes and pushrod holes and opening up those areas. Also considered getting a set of 2.05 valves and having the valve job updated, as well as a deshrouding cut in the chamber.
Of course I'd blend the valve job into the bowls, and do some basic gasket matching of the intake. But beyond that I'd probably not mess with much out of fear of doing more harm than good.