89 360
BJR makes a good point on valves size. Though i suggested 2.02's, I found no real seat of the pants difference. Dyno runs may very well support his suggestion. True, You did say very streetable, I have had no problems with 2.02's in the head @ low RPM's. He is taking a port velocity route over volume. This will really help in the combustion and in a heavy car. Not that A bodys are heavy.
Key thing here is not only velocity, but good flow and amount in volume consumable to make the power. There just needs to be enuff CFM in the head flow to suport the power level is what I'm trying to say.
Is this a roller engine block? I didn't even think of that.
Moper, 360's came with windage trays and the idea of not being designed for it may be true, since 360's were not around when they were put on the 340's, but it is still effective. Weather a MoPar unit or a Milodon, it's cheap or free HP.
Oil control is HP. Many peole don't know about the sheild for the valley to keep oil off the intake. Cooler intake ='s HP.