Thanks for all the replies. I'll address them all in one response, with Cliff's notes below:
My compression ratio will be 8.8:1 compression with the stock thickness head gaskets I will be using. I said "flat top" pistons, though I suppose I should have said "flat tops with valve reliefs". Either way, actual compression ratio will be 8.8:1.
I don't mind having to put 91 octane in it when I head to the track on certain occasions, or if I know I will be going up the Grapevine in 100 degree heat, but I do want to run 87 octane for most of my regular street driving. I don't want to build an engine that may not run well in the future when gas gets even crappier. I'm fine with the compromise for now. I don't have lofty or specific goals, I just want to make as much power as I can with what I've got.
I am adamant about keeping my 2.73s in the rearend. I intend to do a lot of freeway driving and don't want the decrease in fuel mileage or sustained higher RPM operation that steeper gears will result in. I also do not want to install a 700R4 or other overdrive transmission, as my TH400 is alive and well, and is a great transmission that shifts EXACTLY how I want it to, and I am so damn picky when it comes to stuff like that, I don't want to mess with a good thing. Anyway. Sorry for my long winded posts!
As far as installing a different converter, I am not completely opposed to installing a different converter, but I am adamant about not wanting a converter that will require higher RPM low-speed starts, the way that higher stall speed converters do. Perhaps I'm not articulating that well, but I assume you know what I mean. I want this car to drive as stock, with stock, very mild manners in day to day street driving, where anyone and everyone will assume it is stock, until I put my foot down. That's as much for the sleeper effect as it is for my daily enjoyment of the car. I don't want to drive a car that will jump right up to 2200rpm+ with 1/4 throttle at every stop light.
As far as exhaust, I will be using my stock '71 manifolds - I don't know if they're considered HO manifolds or not - They are what came stock on my 280hp 2bbl 455 with 98 heads. They look like a decent manifold, better than some that I have seen, but they are definitely not Ram Airs or anything close to it. Behind that I have 2 1/4" dual exhaust with a crossover pipe, with mufflers taken off a stock '96 Impala, no resonators. I LOVE the sound of this car with these and won't be changing them or the pipe size.
What I want to end up with is a very drivable car, with a responsive engine that makes good, solid low end torque, and decent top end power. I'm not going to be pushing it past 4500 rpm EVER, so any power above that point is wasted. I'm building this engine to last me the next 20-30 years, and fully intend to put 200k miles on it or more in that time, so reliability is paramount, with good power and drivability. I have always liked the way that Pontiac V8s run, and even in stock, low compression form, this 455 was very responsive considering. I'm comparing it to a '72 Lincoln 460 that I had that was just LAZY in comparison, as well as a 402 big block Chevy that was also somewhat disappointing, especially for how much fuel it used! This 455 was always fairly good on fuel consumption for the 50k miles I put on it prior to starting this build. I don't expect that mileage to be the same when I'm done, but with 240k miles it was still getting 16mpg on the freeway going 65mph, so I'm hoping to get at least 14 freeways miles per gallon or so with this combo. I guess we'll see!
Thanks a bunch for the advice. I don't rush into any decisions, and it will still be several weeks before I have all the parts to build it, so there's no big rush. I'd rather do it right than do it twice, you know? This will be a highly detailed semi-show car when it's completed, and I will NOT want to tear this engine apart once it's painted nicely and detailed, so once it's done, it's done.
Also, I will be running stock valve covers on it, but I would like to upgrade from the stock stamped rockers to something a little better - Any recommendations on a rocker that fits under stock valve covers? Perhaps a stamped, roller-tip rocker? Thanks all!
Cliffs:
8.8:1 compression
Stock non-RA exhaust manifolds
2.73 gears
Stock converter or aftermarket that acts as stock
dual 2 1/4" exhaust with crossover
6X-8 heads with 2.11/1.66 valves, mild port job and gasket match
Standard bore 455 with flat top pistons with valve reliefs
Stock 4bbl intake and probable Rochester Quadrajet
Intend to drive this EVERY day and put 200k miles on it
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