thanks for all the replies.
I'm trying to find the info on the compression ratio but I have searched and searched and found different answers.
I have had this motor for a while trying to build the rest of the vehicle.
Let me give a little more info:
It will be run on propane. that was the reason for the cam choice. I remember my motor guy telling me that the pistons I got were domed and would give me a compression ratio of about 10.4:1 Not sure if that is right. but I know that the compression was supposed to be above 10:1. Propane likes high compression since it is on average 108 octane depending on where you buy it.
it will be running the stock exhaust manifold to begin but eventually it will have headers, I was worried about it running out of air so I plan on running this setup for the propane:
IMPCO Propane Dual Twin 2 CT425M 2 425 Holley 4 bbl Throttle Plate 600HP LPG Kit | eBay
Since I already have the two 425 carbs.
Let me know what you think.