My “gut” feeling is that race car you will be happier with a 4500 and specific intake in the end. Results will vary but on a hunch we went with Brett Millers 420-2 intake. Our thoughts were that with our smallish cam (heads flowed N of 400) that the larger plenum would maybe soften the hit….. we we wrong. Way wrong. It absolutely loved it. Maybe too much. I agree with some others. You got some nice parts, you just gotta get them to dance. It’s unfortunate that you didn’t go the dyno route and who CNC ports head and doesn’t know what they flow?? If you built the mill my hats off to you. I was confused enough with the idiosyncrasies of the W8 stuff but with the investment in a new R3 I consulted the professionals. My engine was built and dynoed by Brian at IMM. He actually took control and most likely guided me in the proper direction of “it’ll be fast, but it’ll be fun (lower maint)”. I honestly see with your stuff that low nines will be in the bag.