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Like it says Is big flow #s and even bigger ports the way to go. Along with a low duration but the right lift for combo.

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Just as long as you have enough lift to fill the
cyls.. normally when you have big ports and big flow
it wants high rpm to be efficient.. duration also
tells you about the rpm.. so if your short on duration
those heads might never be efficient ..... JMO

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Look at the cams in the new hemis, high flow, bigish ports and very tiny duration cams give huge HP numbers. You get the best of everything low RPM power and high RPM power without the stupid long duration cams of the 70s. They do get some decent lift but not at the expense of added duration. An average performance cam duration numbers like a comp 280 magnum [Email]230@.050[/Email] would be downright wicked in a 6.1 hydraulic roller.

Another thing to look at and glean information is the engine masters engines and cams, relatively short duration and very high lift with big flow numbers, that seems to be the biggest most consistant part of the recipe the winners use. The winning engines are making incredible TQ per cube and still making very nice HP up stairs.

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Engine Masters are set up for torque.. thats where the
points for winning are... I also assumed he is playing
with old wedge stuff... try using modern rules on
that and see what you get

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Right Wedge it is. But I do look at a lot of the engine masters builds and I notice basically what we are all talking about. Low duration 230-250 @ .050 and 600-900 lift. Also they seem to run the biggest intake valve they can fit. In some of the heads the street class they must of moved guides to get a big valve like a 2.100" or bigger intake in RHS or Pro Comp smallblock heads. With the bore sizes they are running I'm sure they are exceeding the limit of the 52% bore to intake size. All and yes they do seem to get them spun up near 8,000 with a little duration cam. But like Mr P Body said they are looking to make torque and through a certain rpm range.

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Its been a while since I watched much of the engine
master stuff.. but if I recall they are playing in
a certain rpm range so what they are doing works
great for them to make a ton of torque in the low
rpm range... but most if not all of them would be
maxed out in rpm at some low point

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Big Ports w/ Big Flow #s WITHOUT Big Velocity = Big Pig AND Big Disappointment.

If the head's velocity across the lift curve isn't sufficient, the flow #s don't mean anything and the large(r) runner volume just adds to the problem.

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Look at the cams in the new hemis, high flow, bigish ports and very tiny duration cams give huge HP numbers. You get the best of everything low RPM power and high RPM power without the stupid long duration cams of the 70s. They do get some decent lift but not at the expense of added duration. An average performance cam duration numbers like a comp 280 magnum [Email]230@.050[/Email] would be downright wicked in a 6.1 hydraulic roller.

Another thing to look at and glean information is the engine masters engines and cams, relatively short duration and very high lift with big flow numbers, that seems to be the biggest most consistant part of the recipe the winners use. The winning engines are making incredible TQ per cube and still making very nice HP up stairs.

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What controls velocity?

Piston speed and port/runner shape. In essence, the geometric profile (tube) in which the air travels to the base of the valve head. This geometric shape starts at the top of the intake manifold (carb plate) and some may include the shape of the venturi's w/in the carb/throttle body.

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... Where you run into limitations is a proportionally huge port (like a Cleveland Boss 302) on a small displacement motor, it's hard to avoid a peaky (light switch) type torque and power curve with that type scenario. you effectively kill as much duration as you can to try to give it some "passable" bottom end....and (like ford) you gear the wee out of it (4.33 gears, etc).

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Where you run into limitations is a proportionally huge port (like a Cleveland Boss 302) on a small displacement motor, it's hard to avoid a peaky (light switch) type torque and power curve with that type scenario. you effectively kill as much duration as you can to try to give it some "passable" bottom end....and (like ford) you gear the wee out of it (4.33 gears, etc).

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