Was just checking the waters, I like free information so I had to give you a bit more. I have some peanuts but i would have had to epoxy the intake for a nice port match. I think lots of extra advantages by going to the Vortecs, so I ordered them! Keith Black recommends polishing the combustion chamber, exhaust port and valves so I will do that. He also recommends a .040" quench but I wont be turning 6000RPM so that might get tighter. Everything I have read suggests like a ribbed finish on parts of the intake to promote a boundary layer and with that wing turbulence should be great and fuel drop out not a problem.

My initial post was my concern as to if they would bolt up to a MkIV and after reading enough I see that part isn't a problem, however I am still wondering if steam holes have to be drilled, coolant passages ground out, heads can be tapped for MkIV rocker studs or do I have to buy the conversion ones. I'll be able to answer some of that when the heads get here but i figure you guys might have experience!

So! So far I have 454 cid MkIV block, 4.25" stroke crank, 6.385 rods, KB Hypereutectic +.030" flat tops +3cc, L29 Vortec heads 99cc, Dual plane intake, 600CFM Holley double pumper, Long tube small diameter headers, HEI, MSD, I'll talk to a cam company for a cam, I was told I want a 108 degree lobe separation so the cam will be peaky between idle and 3200 RPM.

Exhaust system to augment torque, X pipe or 2 X 2 1/2" inlet and 3 1/2" outlet might work.

I really appreciate your help guys, I don't get to work on the fun stuff often enough!