I recently took a pair of Vortecs to the shop. They did a valve job and also ground down the valve guide boss in order to fit the heavier Z-28 springs on. I also plan on running the Comp Cams Xtreme Energy 262. Is this what you have? Plan on getting Edelbrock RPM Air-Gap Intake and a decent set of headers. I'm also running flat-top pistons which should put compression around 10.3:1 which should be able to run on 91, I hope. Should be a decent combination. As far as rockers go, I am using the original ones that the heads came with. They should work as far as I have been informed. Anyway, still have to buy the intake, cam, gasket kit, and headers. It's going in a pickup. Just curious to see how your combination runs since it is similar to mine. Any HP and torque estimates? Let me know. Thankx.