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port size is important. A very large engine like a 535bb mopar with poor flowing 906 ported heads will swallow most all the cam you can throw at it and it won't pull power past 5800/6000. Try that with a 1970 ford boss 302 (huge Big block type ports)and you have an engine that won't get out of its own way till 6500 rpm. BUT, with the right cam it will make 650 hp at 9500! That was done in a HotRod article back in the seventy s. All they did was blue print the motor, no head porting, put in a big rollercam, and went modified class racing. AS I recall they were shifting that deal close to 10,000 rpm with stock ports.
The 906 head motor has so much port velocity it is hard to screw up with cam specs that are off. I went from a 590 cam installed at 108 to 112 and I didn't see any difference! A 286 @ .050 roller with .750 lift went in, and it only raised the power peak about 300 rpm, but the motor responded with a 5 mph gain in the quarter.
The Boss motor would be very touchy about late intake closing, because there is no velocity to help cover it up till very high rpm. It also will need a lot less duration for the same rpm. The 286 duration cam in that motor might even be too much at 9500, because the ports flow so well they don't need the extra time to fill the cylinder.

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Greg,
Nice reply, very informative. You're absolutely right on cylinder fill and duration. The cam out of my Hemi99 engine has 20* more duration on the exhaust side. They are trying to help the poor exhaust port with it's puny(compared to the intake) valve keep up with the huge port and valve of the intake.

The valve is also being lifted 1.050" so the efficient, huge intake port with a 2.55 valve diameter doesn't need a ton of intake duration to cylinder fill. The exhaust is a different story as it's an afterthought in a pro stock head and needs all the help it can get!

The cam in your 440-1 headed engine probably has more duration @.050 on the intake than my PS Hemi!!