Cylinder head flow - What is crucial in a stocker?

[Adger Smith]

Correct Velocity, Velocity, Velocity
Flow is always talked about & highly sought after, but
the correct Velocity is what accelerates the engine/vehicle and is seldom mentioned.
Just my .02 for free.

[jamie2370]

Originally Posted by Adger Smith

Correct Velocity, Velocity, Velocity
Flow is always talked about & highly sought after, but
the correct Velocity is what accelerates the engine/vehicle and is seldom mentioned.
Just my .02 for free.

THIS^^^^ Bigger does not mean better.

[older racer]

harold bettes, stated , port shape and velocity is everything, don't get hung up on port flow ( cfm).

[HP HUNTER]

I think when your talking about Stock and Super Stock heads you only have a smaller than optimum cross section on most heads anyway, and moving the power up is always your goal as an engine builder. Heres another thing Harold Bettes very often would also say: "It always comes down to flow" And I agree when your talking about a stocker.

[FED 387]

X 2 Velocity

[Bill Diehl]

When the lift is only 2,3 4 or .500 flow is everything...its the _"venturi" effect that speeds up the velocity...when the lift gets to be 7,8 .900 and above the focus is on the velocity and cross section, not flow because the valve lift outpaces the port...in other words it's all relative and stockers are not supposed to alter the ports so the valve job is everything it's the only way to get an increase of anything...legally...my Cleveland heads that I no longer own, they moved 328 at .500 and 349 at .550 and they were legal heads , I taught the owner that owns them now how to do it and he achieved the same results...they fell off like a rock above 600 by design

[Stan Weiss]

Originally Posted by Bill Diehl

When the lift is only 2,3 4 or .500 flow is everything...its the _"venturi" effect that speeds up the velocity...when the lift gets to be 7,8 .900 and above the focus is on the velocity and cross section, not flow because the valve lift outpaces the port...in other words it's all relative and stockers are not supposed to alter the ports so the valve job is everything it's the only way to get an increase of anything...legally...my Cleveland heads that I no longer own, they moved 328 at .500 and 349 at .550 and they were legal heads , I taught the owner that owns them now how to do it and he achieved the same results...they fell off like a rock above 600 by design

Bill,
So you could do nothing to the ports, but made nice CFM improvements at low valve lift with your valve job. Explain to me how those CFM improvements did not increase the velocity in your untouched ports?

Stan

[jamie2370]

Stan, I think sometimes people confuse CFM with CC'S. IMO, CC is not near as important as CFM. Take that for what's its worth. I have somewhat of an understanding of the goal, but it's the process of getting there that eludes me lol. AND...if valve job was the only thing done to Stocker heads, everyones crap would run with mine

[Stan Weiss]

Maybe someone who is doing stock heads will speak up. How far below the actual valve seat into the head can the bottom cuts / angles go? I have seen heads where those bottom cuts went well into the throat area. I don't know if those heads were NHRA legal or not.

Stan

[Bill Diehl]

Originally Posted by Stan Weiss

Bill,
So you could do nothing to the ports, but made nice CFM improvements at low valve lift with your valve job. Explain to me how those CFM improvements did not increase the velocity in your untouched ports?

Stan

I don't know, you tell me.....according to the "experts" and there are many, the flow bench is worthless, I beg to differ, but what do I know?