excalibur and vortec heads compatibility

The big issue with "Vortec" heads is that every engine small block and V6 engine GM made in the late 80's to mid 90's started carrying the term VORTEC on them when in reality the L31 heads are the only really good vortec heads. Heck my 4.3L 6 cylinder engine in my Jimmy was labeled vortec and while the 4.3L engines are great little 6 cylinders that you can't kill easily, I would not rate them as performance engines by any means. Some people say the L31 Vortecs are the best flowing heads GM ever made. Don't know about that as I stick to the earlier engine configurations.

Thanks a bunch ... That's what I needed to know

That's what I got . Can I replace one right ? Are all vortec heads the same as far as compatibly ? Like ford gts ? Found some at a decent price

8 bolts for intake = vortec rights ?

You may not use only one. The intake manifold bolts are different.
If your engine is non Vortec you will need a new intake manifold as the bolt patter is different. Not a bad problem to have is will make a bunch of horse powers for little effort. Did you find a good deal on those heads? Its on my to-do list.