vortec heads

[68stcracing]

Plan to run a limited motor, 6500 rpms max. Are stock vortec valves strong enough for racing?

[dontpanic]

I have been running them, and love them because they make great power for a class that requires OEM heads.
But they will crack if you dump all the water and cook it but they are OK for normal high temp racing conditions like 220F

Brendon

[merc123]

Vortec and double humps were the only racing heads we were allowed for many years and were turning them 6800-7500 for the real bold.