Thanks for the input Tim, I've also seen this before. My concern here is due to the old gaskets as they appear to be "cooked". The right side blew to the outside and when I removed the head the gasket actually crumbled into nothing. This indication of overheat was apparent on both sides. Unfortunately I don't know the history of the vehicle.
These are aluminum heads and I can't see them taking that kind of heat without damage. I just haven't been able to come up with an excuse NOT to let the water flow freely through these heads. Seems to me, "the cooler the better" at least in this situation but. As you said GM likely knows best. My problem is that I love second guessing the big boys designs. :-)
Joe
Sunday, May 11th, 2008 AT 8:23 PM