blue smoke at startup

most performance heads dont use stock type reliable seals for the valves. They are going to allow some oil loss into the chamber and then it gets burned. I had a chevelle with a new engine and world product heads on it. It always burned oil when I first started it and when I got on it hard. Besides, with 143k on your engine your going to have to expect some oil burning from the rings or somewhere.

yeah my guess is valve seals leaking. were your heads new?

well when valve seals leak it's usually when the car sits over nite or for a long period and a little oil seaps into the combustion chambers, then when you fire it up there will be a little bit smoke for a second.. Chevy's are known for this. really doesn't hurt much although IMO it shouldn't do it. Now if you see smoke when hammering on it under load, or idleing, or something then that could mean bigger issues such as rings and such. I would do a compression test on every cylinder and see where you come in at. the smoke is oil correct.. it's not an antifreeze, a/f to rich, or other condition is it.

Valve guides being bad also will result in oil burning at start up - the oil leaks down when the engine sits, and burns off on start up. Are you certain the valve train geometry on your set up is correct? You wouldn't be the first that had the rockers side-loading the valves and wearing out the guides. The old TFS heads had that problem when new.

I suspect there's a bigger issue however - and it's related to the 143K miles. That's a lot of wear/tear on the bottom end. Did you run cranking compression and leak-down tests before you added the other components? Now you've increased cylinder pressure on an already high mileage short block - whatever weak links were there before are gonna start showing up more. I wouldn't even think about a supercharger with an oil burning, oil leaking 143K short block. Unless you're just looking for a reason to rebuild - which it sounds like you're close to anyway.

On the oil leaking - is your pcv system working properly? Many oil leaks have to do with improperly ventilated crankcases building crankcase pressure and forcing oil out where ever the weakest seal is.