besides the caddy 500 doesnt hold a candle to the 472
The 1970 Cadillac 500 will flat-out
smoke any 472 the factory ever built, and in '71 it still had a slight edge over any of its little brothers. In each of the five years both engines were built, the 500 was the more-powerful of the two. They're
identical engines except for the crankshaft stroke. It's like saying the 198 Slant Six is superior to the 225... Maybe the 1970 198
is better than the '76 225, but a lot happened in those years.
Northstars were great when they were new, but they don't age well in terms of servicing. They appeared on "10 best" lists many times over many years, but when they get old they're even hard to disassemble--not that they were a picnic to service new. I wouldn't be surprised to find the early engine management wasn't the best, but you're comparing a VIC-20 to a brand-new laptop in terms of technological leaps in engine control since the Northstar appeared. Regardless, they've always had very good specific output from a well-packaged configuration. Mechanics hate 'em, owners love 'em. And, as 69.5 correctly pointed out, they're monsters with forced induction and a good aftermarket tune to account for it.
Regardless of engine installed, it's a Fiero... basically a Chevy Celebrity built backwards with leftover Chevette bits to steer it. The only one worth having is the '88, whose suspension was completely redesigned and can be made into a credible corner burner. Typical of GM, as soon as they got it right... they freakin' cancelled the car.