4 Barrel

Stock 273, 2 barrel motors were rated 8.8 to 1 from the factory. Not exactly low compression by todays standard. A head gasket change could easily get the motor to 9 to 1 which would be perfect for a street motor. Aside from the valve train issue where did the carb come from? Edelbrock, Carter 9636, stock 273? Been my experience with 273s that the Edelbrock 600 out of the box is pretty much right on as far as a baseline. FWIW I’m running a Carter 9636 on a 273 with the stock CR, stock cam, Edelbrock Performer, Electronic ignition and the Commando single exhaust. It by no means is a stump puller but it does have a little gittyup.