Substituting Shelby block for Iron SO

[SFfiredog]

Hi Wayne,
I think both Keith Craft and Kuntz & Co have CNC programs that will get 380 to 390 cfm intake and 270 to 275 exhaust of a set of E-brocks ($$$$!!). Your E-brocks have excellent flow #s. My personal experience has shown that the nail head shaped (intake) valve does work better at high lift numbers on a non-tunnel port FE head. The tulip shape has slightly better #s at the low to mid lift range. I imagine this is because the tulip shape helps transition the sort turn radius at lower valve lifts. The nail head makes more overall power though. The tunnel port head still seems to like the tulip intake valve. Once again, because of the sewer pipe shape and relatively tight short turn radius the tunnel port head has the tulip shape helps low to mid lift flow but because of the size and location of the port it also helps high lift # as well. I am still experimenting with both valve shapes for my tunnel port as well as 30 and 45 deg valve seats. The 45 deg seat definately flows more at high lift on the E brocks. I will keep everyone informed of what I find works best. The exhaust valve on both heads seem to like the standard nail head shape.
I really don't know why I'm going to this extreme on my motor. It will already have more power than I will be able to put to the ground. I guess it's just in my blood to make it better!
--Mike