Payen AF470

[ADRay]

doing the head gasket again, this time trying out a Payen AF470.

I've heard conflicting info that you have to do an initial 40 second break in with no coolant... or distilled water... or coolant. gotta love the www...

anyone have experience with them?

[MiniDave]

I also have read conflicting ways of doing it. I now torque, run to warm with coolant, let cool overnight and retorque.

However, my racing friends say start, run till 140* on the coolant, shut down and re-torque, then warm up to operating temp. Let cool overnight and retorque one more time, noting whether you gain any further movement. They also only use ARP head studs, which torque to like 55ft lbs vs 45 for stock ones.