Are 049 heads good?
For mild street and budget bracket big block Chevy 454, the factory iron 049 heads are outstanding; if they were cast in aluminum, they would be ideal. Big block Chevy 454 heads feature what are referred to as good and bad intake ports.
Are 049 heads open or closed chamber?
290 & 049 heads have oval ports. 290s are closed chamber, 049s open chamber. They both flow similar numbers until .
How much power does a 781 head have?
The 781 heads are the best cast iron large oval port heads GM ever produced for the big block Chevy engine. They are worth rebuilding and respond well to pocket porting, bowl blending and larger valves. They will easily support over 500 horsepower.
What size valves are in 781 heads?
The 781 heads have 256/114 cc port size runners, with 118cc combustion chambers. The 049 heads have 255/119 cc port size runners, with 122cc combustion chambers. It’s really a toss up on which ones to use as the 049’s flow more but the 781’s will give a little more compression.
What is the difference between closed chamber heads?
Closed chamber heads have a combustion chamber that resembles a bathtub, has quench area on both sides of chamber. Open chamber heads have the spark plug area of the head laid back to the edge of the cylinder to form a larger combustion chamber.
What are peanut port heads?
For the uninitiated, peanut port refers to the small, oval-port heads used on the Gen-V 454 truck motors run prior to the introduction of the Gen VI in 1996. In addition to the less-than-ideal, peanut-port heads, the Gen-V motors were also saddled with hydraulic flat-tappet cams.
Do cylinder heads increase horsepower?
In addition to revising the camshaft events, one of the best methods of bolt-on power relates to the cylinder heads. Improved throttle response, ‘fatter’ power and torque curves, and peak horsepower can all be generated through selecting the right cylinder heads for the engine combination.
Which is better 049 or 049 cast head?
They both flow similar numbers until .400 lift when the 049 head will flow better at higher lifts because of less valve shrouding. This is especially true when 2.19 intake valves are installed.
Which is the best head for a 396 engine?
Even better is if you can run the open chamber heads, but like mentioned in other posts I’ve never heard of them being on 396 engines. If you have to run oval/closed heads the 063 or 290 are nearly identical and flow decent.
Is the 781 head the same as the 049 head?
Both 781’s and 049’s are open chamber and they’re virtually identical. Sounds like the ones you’re calling 049’s are a closed chamber head. Gary you are right, I must have had my numbers wrong.
Can a 396 block be punched out to a 496 bore?
Be aware the ONLY 396 Block which can be punched out to a 496 Bore is the 3855961, 396/427, 65-66, 2 or 4 bolt Casting which uses the Groove in the Rear Cam Journal, other words, you have to use either a 427 or 454 block. I flowed a pair of 702 heads for a friend of mine about a year ago.