Cylinder head flow - What is crucial in a stocker?

[Doug Hoven]

Originally Posted by Bill Diehl

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?

I recently had the head off of the 6 cylinder on the flow bench. Boy were we surprised how good the head flowed even at the .388 lift I am allowed. Flowed better on the intake than a stock small block head, and the exhaust flowed 80% of what the intake did. The reason it flowed as good as it did was the fact that the intake ports(there are only 3 btw) are WAY too big. While I do believe flow is very important, when the rest of the engine (in this case the 200 cfm carb and small cam) can't support the flow you can get out of the head, you're going to run into an issue with air not moving fast enough. There's a reason the most common aftermarket chevy 6 cylinder head mod is to weld in a "lump" to the bottom of the intake port to take up some volume. As odd as a chevy 6 cylinder may be, I can only imagine the same principal applies to a wide range of combos.