[MrPbody]

Rivguy,
While I cetainly love the style and pinash of the mid-60s Rivvy, it's not on the list for a couple of reasons. Mainly, the nail-head is a slug. And fragile, as well. They were okay when first introduced in the early '50s. Actually, pretty much "leading edge". Small block Chevy and Pontiac V8 in '55 made ALL the Olds and Buicks of the day obsolete over night. The '59 Cad was the first real challenge to them from within GM.
Rivieras are VERY heavy cars. A '67 GTO with all the trimmings (including the "switch-pitch" TH400 you said wasn't available in Pontiacs), and the "full throttle cutout switch" for A/C, weighs in about 3,600 lbs. dry.
Please don't take this wrong. I LOVE the Riviera. Especially the '63-'65 models. But Rivvy belongs in the same category as Grand Prix and Toronado. it is a "personal luxury car", and a damn fine one, at that. Perhaps the nicest of the three GM offerings. But it is NOT a muscle car, and lucky to be considered a "performance" car.
I read all the reports of fast Buicks. Well, I've seen a couple. But only one that sticks out in my memory. That was T/A Performance's (Phoenix, AZ) Sport Wagon. It was going low 10s when I saw it 15 years ago. I spoke to them a couple weeks ago, and it is now in the high 8s. They claim it to be the fastest normally aspirated door slamming Buick (powered) in the world. If that's true, it's nowhere near the top of the heap, as there are multitudes of Chevys that go 7s in similar configuration. I saw no less than 7 door slammers in the 7s at the last TriPower Nats at Norwalk (ALL Injun engines). There was even one '69 Grand Prix, all steel, and IRON heads, going 8.0@180! That one DID have a nitrous unit on it... It was called "Purple Prix". I have some pics.
You know, of course, '69-'72 GPs are on the same chassis as Rivvy, right? It's known as a "G-Body". Monte Carlo shared the platform, as well. The A-Bodies (Skylark, Tempest, Chevelle, Cutlass) have a 6" shorter wheelbase and are at least 500 lbs. lighter than the G-Bodies.
They get on me all the time for loving the Pontiac. I understand your plight. But realism and experience must play a role here. The Buick is one of the nicer cars out there. But fast? Not really, at least in any volume. People don't race dynos or magazine tests. They race cars. I promote the Pontiac to keep the history alive, and to break paradyms. Pontiac's racing history is as glorious as any manufacturer in the world, and better than most. If Buick had a racing history of any kind, I would promote that, too. The handful of fast cars they built simply aren't enough to consider.
PAX