Thanks for the good info, Bob. I remember one car, a '61 Pontiac that had a dealer-installed "hop-up" package that would have been neat to see in Stock, but since it was never a showroom option, it never will be, I'm sure.
It was a '61 Catalina 2-door hardtop driven by Charlie Mitchell, who was a new car salesman at a Pontiac dealerhip in England, Arkansas, and one of those cigar-chomping, larger-than-life characters that are so rare, nowdays.
The engine was a high-compression 389 with three two barrels on an ALUMINUM intake manifold, with special big-valve heads and streamlined exhaust manifolds. It was the last gasp for the 389 before the 421's came on the scene, and ran 13.30's with a 4-speed. It had a decal on the front fender, "Ray Nichels Engineering" (a NASCAR guy, I think,) That engine was rated at the time, at 363 horsepower, but I have also seen it referred to as a 369 HP motor.... dunno which is correct.
It was the scourge of Stock that year, locally, until a dirt track racer showed up one day with a '62 Plymouth 413 cross-ram car with a 3-speed stick; instant 12.90s...
)
Charlie traded in his '61 for a '62 421 and raced for a long time, but none of his cars ever impressed me like that white '61 Catalina... it just LOOKED "fast"!!!!!!!!!