[Keithc8]

What we refer to as our stage 2 head is our in house work that icludes: checking and sizing the valves to the guides, our flow tested multiple angle valve job, special back-cut angles on the valves, hand porting the head to flow go numbers in the .300 to .600 lift range where most street strip heads will be most of the time, cc combustion chambers and mill to spec, flow check the intake and exhaust flow, deburr and chamfer the heads after milling and porting, check assemble heights, check valve springs for proper pressures for the application, positive stop seals, stainless one piece valves, spring seat cups, 10 degree retainers and 10 degree steel locks, dual valve springs. We then completely assemble with a build sheet on the heads. We use all of our own parts and start with a bare Edelbrock casting. We even have the intake valves made for us with the proper seat angle which is different than the factory for better flow. When you have been working on FE heads for 20 years you better have learned something about them. As far as the flat-tappets goes, if it is a hydraulic flat-tappet i think you will loose about 30HP but if it is a solid flat-tappet and the right one you may loose about 20 HP down low but may pick some up above 6000RPM if everything is the same. I hate having to break the camshaft in and then worry about the lobe going flat down the road. this is reason we run a lot of the hydraulic rollers. Hope this helps a little. Thanks Keith