The numbering system that is mentioned may not be exactly the same here in Canada, because the number of the 200-4r that I got out of an '88 Grand Prix with a 4 bbl SBC is a 13 digit number, not 15 as stated. The ID is HTF, and will end up behind my warmed up OHC6. I'll be making a fair bit more hp and torque than the SS "flywheel" figures, but I'm not at all worried about it handling the power in stock condition. Not to start an arguement, but I'm pretty sure that the numbers given are at the rear wheels. At least I hope so for the sake of all those Monte owners!
My old stovebolt 235 in my '54 Chev truck made 245 ft.lbs of torque at 2000 rpm and 160 hp at 3600 rpm, with an extremely mild cam, siamesed intake and exhaust ports, and the stock exhaust manifold - on the dyno, with accessories and full exhaust system. Much as I like the thought, I don't think my engine is making more torque and almost as much hp as a modern engine that is about 30% bigger.
Strange as it sounds, I've heard reports that the 200-4R is easier to modify for the 500 hp range than the 700-R4. That, plus the smaller size and what I consider to be better gear ratios and of course the fact that most have the B-O-P bellhousing, to me makes the 200-4R a great choice for updating the FGF.
From what I understand, a post '86 tranny has all the factory improvements except the improved front pump.