Should be 74cc
The combustion chamber size of the heads with the casting number 376450 is 60cc. It is possible to install larger valves.
The chambers are 60cc. The heads are from 77-78 307 engine.
60cc
stock 350 heads are 72 or 74 cc
The word 'vortec' is the name of the cylinder heads used in Vortec Model engines in the year 96'+ The engines that use the Vortec cylinder heads are the 4.3L Vortec, 5.0L Vortec, 5.7L Vortec, and 8.1L Vortec. They were only put on Gen I small blocks. If they are any other size Chevy engines and still retain the Vortec name then it's purely a marketing name, the same goes is it is later than a Gen I engine. For example the new 4.2L I6 from GM retains the name Vortec, but it does not actually use Vortec heads as these heads were only made for OHV engines, and the I6 is an OHC engine. The Vortec heads are based on the LT1 and LT4 head after they were discontinued along with their reverse flow cooling design. It is simply an effect made in the head similar to a vortex to better atomize the fuel and air intake charge when entering the combustion chamber, it is not a different type of motor.
The word 'vortec' is the name of the cylinder heads used in Vortec Model engines in the year 96'+ The engines that use the Vortec cylinder heads are the 4.3L Vortec, 5.0L Vortec, 5.7L Vortec, and 8.1L Vortec. They were only put on Gen I small blocks. If they are any other size Chevy engines and still retain the Vortec name then it's purely a marketing name, the same goes is it is later than a Gen I engine. For example the new 4.2L I6 from GM retains the name Vortec, but it does not actually use Vortec heads as these heads were only made for OHV engines, and the I6 is an OHC engine. The Vortec heads are based on the LT1 and LT4 head after they were discontinued along with their reverse flow cooling design. It is simply an effect made in the head similar to a vortex to better atomize the fuel and air intake charge when entering the combustion chamber, it is not a different type of motor.
if you make the combustion chamber smaller for example by shaving the heads when the sparkplugs ignites , the piston will get pushed down harder there for make your engine go faster .In short, reducing the combustion chamber size increases the combustion ratio which increasing the explosive force of the air fuel mixture when it burns. The negative side of this is fuel with a higher octane rating will have to be used to run the engine.
Depends on the heads. The size is different for the exhaust valve and the intake valve, and different engines have different size valves. The valves are mechanical devices in the engine heads that open and close. The intake valve opens to let the air/gas mixture into the combustion chamber,. Both valves close the combustion chamber during the compression stroke, and the exhaust valve opens to let the burnt gas out during the exhaust stroke.
76cc
You will need to have the heads for the 305 bored out to the same size as the 350. I disagree: you can use the 305 heads on the 350 block but you will increase compression as the 305 heads have a smaller combustion chamber. The critical dimension is valve clearance. If compression ratio is a critical consideration, different pistons may be available which will bring the combustion chamber back to size. the 305 is from the 3.671 inch bore family. The 350 is from the 4.00 inch bore family. All small block heads have the same bolt pattern.
1993 350 what? check auto.consumerguides.com
58.cc low torque swirl chamber head