I did 76 truck 318 with 340 cam, 360 heads intake and 305 carb, stock single exhaust, it definitely picked up a bunch of power. My cousin put his dads duster 4 speed back on the road with smokey 318 bottom end with his dads fully ported T/A heads, LD340, 750 and some cam laying around, sounded pretty healthy, it worked really good especially when he swapped 3:23 to 3:91 that really woke it up. Plus he needed to fix the 340 short block on his late model so he just swap carb and intake on the his duster 318 and kept up with the pack.