if they are that old nort you are probably right.... if you dont run salt... they could potentially last indefinately but i ere on the side of caution.........and a roached motor just plain sucks........

I spoke to Daid at CMI yesterday about testing, he said they use 60 psi air pressure in a tank of water. That's how I did mine. I also used 110 degree water.

60 psi seems a bit high to me but whatever...... and testing in a tank full of water would eliminate some of the danger id lay dollars on dimes that the tank is big
i certainly wouldent be standing beside it at that pressure........not with air anyways........

They won't explode. If anything they would pop a leak with excessive pressure. I used 40 psi to test mine and I agree that it makes more sense to use air. The slightest leak will be visible as a stream of air bubbles, no matter how small. Trying to monitor water pressure changes from a tiny leak seems impossible and trying to keep the jacket pressurized with water while keeping the outside completely dry to watch for wet spots seems very difficult. If CMI uses air pressure then that is how I will continue to test my headers.

Can someone offer insight into what damage could be caused from a leaking header . I understand the potential for hydraulicking a valve , but if the leak was small and caught right away what should i be looking for ?

a leaking header or manifold can be disastrous........cool or cold water touches a hot exhaust valve and the exhaust port on the head instant roached valve,,s or head......worst case senario is a hydraulic-ed bore
usually a roached block to go with the head and valves and on and on if your running wot when it happens cant react fast enough

silly me didnt read all of you post ride

You must be scared to death to stand next to a 150 psi air compressor.

now that's funny!!