Paul, what’s the highest octane is available to you. Here on the island, readily available is 93. I’m running an 11-1 engine with it now. The 360 is zero decked and a thin head gasket is in use.
For me, the use of a dual plane vs a single plane is more rooted in the intended usage of the car. So far, what I have gleamed off the forum from the been there and done that is the RPM intake has an edge over the single plane down to somewhere around the low 11 second range. But this is also dependent on what’s being done with the car and what parts are used under the intake & the weight of the vehicle.
The wife’s Cuda is using a dual plane and has 3.55 gears on 26X10 tires. A very similar cam to the cam card above.
Gear ratio, tire size, trans and converter (if it applies to other readers of the forum) need to work with the camshaft with the CID of the engine.
Fact, trying to push a 3400+ lbs car into the 11’s requires a bit more power than a sub 3000 lbs car does.
As I show above, the dyno chart of the 408 that created 460 HP and mounds of torque, will be a fun street car. Going with a bigger cam will push the power leaks up the rpm scale. That was done with a rpm intake and a 750 w/an inch spacer IIRC.
Going up in cam duration to a 250@050 will get you to your 6000/6500 area a lot better. (Not Guaranteeing that peak power is there.) And around here (IMO) the engine will like the single plane better when under a W.O.T. condition.