Originally Posted by SoCa06Z
what were thought to be Vortec heads are actually old swirl port heads that aren't worth a damn past 4k RPM.
I was gonna say the end design on the cylinder head didn't look correct and the intake bolts had the 12 bolt pattern and angle not the vortec's 8 bolts.
If you can source some vortec heads that aren't cracked for a good price grab em. I have a set on my 355 in my oldsmobile and love them. What an upgrade from the 441s.