Flowing a intake manifold on a flow bench

[91daytona]

Does anyone have pictures or a detailed description of how an intake manifold is mounted on a flow bench for testing?
I assume all the ports besides the one being tested are blocked off.
Can you install a four hole radius plate on the carb base or should it be a open radius plate?

[revolutionary]

You can either bolt it to your head or flip it upside down and bolt the carb flange to the bench

[David Redszus]

Whenever I have bench flowed intake manifolds I have done so with the manifold attached to the head. Block off all other ports or simply leave the valves closed.

[91daytona]

That's how I have been doing it also but I know there will be times that a customers heads will not be available. I will make an adapter and do some testing. thanks.

[David Redszus]

When it comes time to flow the exhaust ports, does anyone attach the exhaust header and pipes?
If not, why not?

[1989TransAm]

"When it comes time to flow the exhaust ports, does anyone attach the exhaust header and pipes?
If not, why not?"

According to "Exhausted" The first 8" of the header is the most critical part. So if that is the case why not attach a pieced of pipe with say a 90 degree bend with a total length of 8" or so. Seems to me that would be more realistic.

As to flowing intake manifolds on a SF600 one of the guys in our club made an adaptor that bolts on to the flow bench and then shaped to fit on in this case a SBC intake manifold one port at a time. The bolt holes are slotted so that you can adjust for alignment or to fit the adjacent port. Wish I had a picture to show as it is a work of art.

[91daytona]

I would like to see a picture of that.

[rob vine]

years ago flowdata or quadrant scientific had a flow bench that mocked up two heads and an intake on it - i had some liturature on this from an old pri show in cinnci - i wonder if they sold many and how well they performed - curious ,as i would like to know- i think the idea was there and always thought that it would be good for testing intakes

[David Redszus]

If a cylinder head is to be tested with the intake (or exhaust) manifold attached, it is wise to remember that the runner volumes from the other cylinders will act as a Hemholz resonator and will "tune" at certain air speeds. And that some of the other valves are open while others are closed. This effect will certainly skew measurements.

Now the question becomes whether or not a flow bench can produce the necessary air velocites, as seen in a running engine, that will accurately replicate the tuning effect of branched pipes.

SAE paper 720214 "Design refinement of induction and exhaust systems using steady-state bench techniques", does a nice job of exploring the branched pipe effects.