another 383 build up Q

Love your name...lol. (I get motion sickness...)

I'd have 2 very different buildups. Using your "street car" plans, first no boost. The best way to make power on the street without compromising drivability or fuel type is big inches. You have the 383, but it needs attention. I would find a 400 to use as a core. The biggest bore (least valve shrouding as BJR said). There's awebsite 440source.com that has many ideas on strokers. Now, if you're dead set on running a sleeved 383 block hard, then you can get 496" out of it with the kit 440 source offers. I havent built one, so I dont know personally, but I've heard you must run an external oil pickup (read as Milodon pan/swinging single external pickup and Milodon oil pump) even with the Chevy rod pin size that set up uses. Now, keeping things simpler..A 400, with a 4.15" crank, will also give you 496", but no strange oil system stuff. A typical Hemi pan, 1/2" pickup, and HV pump will cover the oil system. A N/A 496 needs heads. So I'd use in pecking order Indy SREZs or the MP stage heads BJR says. A word of caution tho, I have heard of major problems with the Stage heads..Both iron and aluminum versions. Not all the time, but enough. In any case, I would buy bare castings, and assemble them in house, correcting as they go. A solid cam or solid roller is how I'd cam it. A complete, dyno'd and set up engine like this would run roughly $12K, with headers, ignition and carb. Pump gas, 600ish hp, 575ish tq. on pump (92) fuel.

For boost, I'd go a Callies 3.75 crank, Eagle H beams, dished pistons, and the SREZs. Keep the static ratio down to 8:1, the chambers may need some enlarging to do this, as I would want to keep the quench area of the piston intact, and keep the quench tight.(helps stave off detonation) I'drun 2 smaller turbos with an air/air intercooler. I'd also use billet main caps, and a girdle. the larger Hemi oi pickup and HV pump. With the turbos, extra block work, and piping, plus a controller (Megasquirt?) you're looking at least $15K for a dyno'd monster. I'd estimate hp from 700 to as high as the turbos can make. Similar "street" versions can make well over 1000 after careful tuning. Really, the boosted model needs a ton of "in car" dyno (chassis) work to get all dialed in, and that's a lot of money.Same with high pressure fuel pump, braded lines to and from, coating the IC plumbing..It's a lot of extra $$ and work.

Just curious, where you going to run a car like that anyway? My meaning is, are you being honest with yourself as to what you plan to do? Because a N/A street car (10.5" treaded tires, 3.91 gear max, leaf springs, stuff like that) can run way into the 10s with 550 hp. And it will be a scary fast ride around town, and you'll have to be climbing around a roll cage to get in and out. Just my $.02.