When I originally bought my '63 Effie ICB, it had had a '64 PI engine swapped into it. The cam was changed, and it had long '63-'64 iron 427 exhaust manifolds. It also had a 406 triple carb set-up on it.
It was quite tired, so I pulled it and put a vanilla parts 390 in that I put together from garage corner parts. When I tore the PI engine down, it had a C4AE-A block with the webbed main bulkheads and cross-bolt knobs and was through-drilled for 'juice' lifters. However, the passages in the tower in the back of the valley were not drilled, so it was, in effect, a solid-lifter block.
I went through it pretty completely, putting in cross-bolted mains and opening up the tower passages to supply the squirters to oil the rollers for the Comp solid roller cam. I also bored out the cam tunnel to install roller cam bearings and regrooved behind the bearing shells to supply the mains without any loss at the cam bearings.
With Ross pistons, and bores capped with Dove 'D5' heads, we saw 500 horsepower at 7200 on the first pull after 15 minutes of break-in on the dyno, using a Dove spider and a dyno 850 carb
I believe the C4AE-A is as good a factory 390 block as was cast. It was on the border of being 'iffy' if I took it out to 4.13 so I compromised at 4.080.
KS