My 327 its pretty much a stock L79 long block with a bigger solid lifter cam. it has 10.96:1 compression hardly any porting done to the 461 double humps. 2.02/1.60 valves performer rpm and 650 DP. Anyone have a certain plug they like to run with the old 461's? Right now I have ac delco marine plugs to get down to a cooler range. MR42S I think is what they are. The coldest regular plug is an R43. Any suggestions would be great.