Thread: Combustion Chamber size

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Hi, I have a set of heads i took off a 427t motor that i'm gonna use on a 505 tall deck motor i'm building. The casting # on these heads is 343772. They have LARGE oval ports and 2.06/1.72 valves. What is the largest set of valves i can put in these heads? 2.19/1.88? Does anyone know the combustion chamber volume on these heads? What is the intake runner volume?
and as always..thank you for your replies

the valve spacing is all the same so if you want 2.250 and 188 or what you want for valve size. the heads will have to have some work in the bowl the bigger you go so so i would stop at 2.190 but have seen 2.250 in them your call

Assuming i can get the intake and exhaust runners to flow enough air...Are 2.19/1.88 valves big enough to feed a 505cu motor that would not be run over 6000rpm?

thanks for the reply pat

the 188 ex is ok have used them in 600 engines you may see some hp with a1.900 but may not be that good to do with a stock head but they can be cut for them the 2.250 intake will work good but they may not be enough in the bowl to cut them out that big. i have cut gm heads in half you will have to watch this if you try to cut them way out. and work the bowl out you may have junk. 2.190 in and 188 ex will work fine try a set 11/32 stems if you what some more flow and help with mass what you need to ask is if i put the big valve in can i cut the the bowl out big enough to make the heads work better ?? you can put very big valves in but if you can not bowl them out much it will be bottle necked at the bowl so to be on the safe side 2.190 and1.88 with out seeing the heads