273 Rockers on a 1971 340

My engine is a '71 340 with 10.5:1 (stock) with 2.03 J heads. Have a Comp Cam XE262, HP exhaust manifolds (69), and a Holley/Edelbrock six-pack. Automatic 727 with 3.23 8 3/4 sure grip. Got a great deal on the rockers and wanted to use them. Pretty much a stock engine with a couple of add-ons.