I stopped at a local yard today and seen a pair of vortec heads on the counter. The yard sells them at $150 per pair. Sounds like a good price, I've heard there is two different versions with one being much better, does anyone know which casting to look for?

The 5.7L 906 and 062 Vortec castings are what you want. graemlins/thumbsup.gif
An error was made last year in one of the car magazines that stated one casting was "better" than the other. That statement was wrong and was retracted the following month.
Stay away from the 520 and 059 Vortec castings! They're from the 5.0L (305) truck motor.

The 062 Mexican casting have smaller intake runners 159 cc as for the 906 and non-Mexican 062 have 170 runners graemlins/thumbsup.gif

Originally posted by CNC BLOCKS N/E:
The 062 Mexican casting have smaller intake runners 159 cc as for the 906 and non-Mexican 062 have 170 runners graemlins/thumbsup.gif -
Hmmm,,,, Apparently not all Mexcian casting are the same.
I just finished a set of 062's for a customer & the Intake cc'd at 169 :confused:

do the 520 and 059 305 castings have the same port volumes as the 350 but with smaller chambers?

All vortecs are supposed to be created alike except the 305 castings have 58cc chambers instead of 64cc :confused: