I run this same intake . The cam is larger but ground on a wider LCA. 285/292@112 in at 108. it is 572" so I have not reduced the plenum. The timing is crank trigger fixed at 32-34. While it starts fine warm it is very difficult to start at 50 degrees or less. By accident last year I stumbled on to something. I have a set of machined aluminum carb covers to keep debris out when it's parked. Getting ready to make a run the engine started quickly, than went pig rich. You guessed it, forgot to take the covers off. In the fall again it wouldn't start. I was afraid I flooded it so I pulled the plugs, 6 were dry , 2 were wet. Swapped plugs still didn't want to start. Put the caps on, fired right up. I used to crank it first w/o spark. This resulted in hard starting. One time it resulted in this.
Doug