'Budget' 340 build suggestions

I'd go with the KB243s and those 318 rods. Have the rods redone w/good bolts and the deck height set to 9.609 if possible (check decks for that first). Have it line honed, square decked, bored and plate honed, crank indexed, ground, and polished, and internally balance (rods and pistons are LIGHT...). That gives you flat top piston above the deck by .008". Run the std Felpro blue or anyone else's stock gaskets and you'll have right around .038 quench. For heads I'd run EQ Magnums with the LA intake pattern. MP or Hughes valve springs, Stock Magnum rockers. Run a hydraulic cam like the Engle 4420H (.499 lift, 268°, 228°@.050 w/1.6s), your intake and carb. I'd think that should be very close to, or exceed 400hp and be good on pump premium, maybe pump 89. In terms of costs... lower end machining (no assembly... assuming you'd do that...) $2100. Parts $3000 give or take (including carb rebuild kit and everything new but lower end cores...) for a total of $5100 plus shipping/handling, assembly, run-in/dyno session, etc etc etc...lol.