Like Mark Jones, I work in a machine shop, get asked this all the time. It depends. A complete block with tin etc, if everything specs good, saves $. If the bore is in spec, hone and new rings. 400 are thin wall, so not wise to bore over to much, so if an overbore is needed, shoot for .010 over, which I would torque plat hone, no boring. Takes longer, but safer. Rebuilt 194 Heads three angle valve jog, guides, seals, and springs to match a conservative (230@ .05) cam, gasket matched, heads and intake. Call a cam mfg, tell them your specs, and use there expertise!!! All the blocks I build myself, I do the prep, saves time which equals money, the more you can do the less it costs. A dual plane intake, Holly 750 vac secondary with the secondary block (not the plate,) 1 3/4 or 1 7/8 long tube headers, three inch all the way back, free flowing mufflers. The only other thing I would spend money is a AF gauge like AEM, to tune the motor in the truck. This is where you get the instant throttle response, best gas mileage and drivability. I installed mine right in my dash. A stock or mostly stock long block rebuild will be between 3500-6000, (depends on parts,) complete, balanced, (a must!!). Run in on engine stand, and tuning can easly be min $500. A little more then two cents. AF gauge by lighter. Runs down the road at cruse right 14.1. Full throttle vac secondary's all in between 12.3, and 12.6. Last pic Elk below the house.
