Best 273 and 318 builds (NO 360's please)

my 318 combo will be Iron Ram 202 heads, Hughes Engines whiplash cam, flat top pistons for 9.25 compression so I can still run on 91octane. Stock 2500 converter and 3.23 sure grip in my 68 Barracuda. 3126lb car should run low 13s and be plenty street able.