Block manifold and water pump after heater delete?

[garyd1961]

Originally Posted by ratty69

So if I understand this, the bypass hole exists in all blocks but only in pre-vortec heads. How about laying a pre-vortec gasket on a vortec head and drilling the missing hole?

Thinking about upgrading to vortecs in the future so this is good to know...

I know the hole exist in the water pump and the block but I'm not sure if it goes all the way to the head on a vortec block or not. I do know if you run a wire up in it, it bottoms out. I wouldn't just drill the hole in the heads until I found out why it was deleted in the first place. You may drill into the wrong thing or cause the head to crack. Factory vortecs are pretty thin.
Some say you can just drill a hole in your thermostat but it didn't work for me. I could drive for a little while and then my gauge would jump all over the place. I installed a bypass hose and haven't had a problem since. I even switched from a 180 thermostat with a hole drilled in it to a 195 with no hole and the gauge is still steady as a rock.