If you buy the block you need and commit to the 406, you will love it. In a bracket engine they are sharp and full of torque. For the money they are my favorite engine. I built a pump gas GM block 406 with Brodix track one heads (ported) and with a solid lift cam that was 257 265 at .050 and put it in a camaro with a glide and 5000 stall and 4:30 gears and it ran 10:60s with a best of 10:55. It far exceeded my expectations!! It was a 3200lbs car with driver! They heads flowed 300 at .700 lift. on the intake. Oh......950cfm holley.