11.4 to 11.5 pump gasIs this going to be a high compression engine or a pump gas engine. If you check what is run on 383's and 400's most run large intake runners so I would go with the 210's. Years ago I built a 383, 9.5 compression, mechanical roller cam 240/250 duration, Victor Jr. with a 750 Speed Demon. I went with the iron head Motown 220's. The higher the duration the bigger the heads. If it's a street only car I would use the 195's.