Buy a GM 383 short block and have your heads rebuilt with port job and better springs.This will work great with stock tpi.

 

SMOG legality is also what you loose.... If he is in Denver then they have a smog program that would fail the car immediately when they saw a carb on it... If you don't have an inspection program in your area it's not a bad choice for 'cheap' power...

Biggest cam and tune it doesn't really mean anything - the big cams move the power band up in the RPM range and that's where the TPI falls short - can a really big cam be tuned with the TPI? Of course - will it perform well? Probably not - your better off deciding where you want the power and how you'll drive the car then build around those parameters...

My guess is you want a good a street car that will rarely see the strip or high RPM road course action - that to me means build good torque from 1800-3500 RPM or so - which means sticking with a cam around 210-215* duration, ~112 LSA and as much lift as you can get while still controlling the valvetrain (which means new valve springs/retainers/locks and rockers). You'll want to do some clean-up porting on the heads, and on the upper and lower intakes at least.

The short block - cheapest would be to just rebuild the engine you have with some basic parts like: pistons - H345NCP .030 over flat-top pistons ($120), Cast rings w/Molly top ring ($45), new cam/rod/main bearings ($80), FelPro complete gasket set ($130), and a brass freeze plug kit ($15). The machine shop would have to clean the block, bore and hone .030 over, install the cam bearings and freeze plugs, press the pistons off and new ones on, and I'd have them check and polish the crank just to make sure it's not slightly worn undersized. The machine shop bill will be around $350-ish for that work and add another $150-200 for them to assemble the short-block.

The next would be to step up to a 383 kit which would you will need a new crank ($200) (different pistons but about the same cost) and then to have the machine shop clearance the block for the stroke ($80-100) and then balance the rotating assembly balanced ($200) - I'd probably opt to get a new set of stronger rods for around $190 instead of relying on the old ones or reconditioning them with new bolts.

Hope that helps.