[Steve C.]

On the subject of the intake/exhaust flow ratio. Here is what Harold Brookshire from UltraDyne said on the subject within a post here on PY:

"On most cylinder heads, whenever I have around a 75 percent exhaust-to-intake ratio, I use an 8 degree bigger exhaust cam.
If the ratios under 70 percent, I use 12 degrees, and around 80 percent, only 4 degrees.
Whenever the ratio gets around 85 percent, single pattern cams seem to work as good as anything."

BUT this was not specific to Edelbrock heads at the time. That could be a general statement from him with factory heads in mind.

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