How hot can aluminum heads get before they warp?

[Stang_ROTY]

YES! SUCCESS! IT's WORKING! That fan and shroud made a huge difference. I can actually feel the difference myself standing above the motor. I think that did it Chris. You are da f#&%ing man! I filled her up with water and put the cap on tight. Once I started the car and ran her the temp gauge got to about 150, then 180 and I noticed the upper rad. hose was hot which told me the thermo. opened. Then it creeped up to about 190 and the lower hose was hot and the temp. lowered back to 180 on the dot. I started to rev her to about 3500 and it creeped up again but never got over 195. Beautiful. She even sounds better now that I changed the oil (it was really shi##y). Thanks to everyone! Chris, you are for real. I think I'll actually make to Ford Day at Lebanon Valley tomarrow. So what do I do now? Do I take the water out and fill it wth antifreeze, or leave the water in it? Thanks again Chris. You were right. Now hopefully when I drive it the temp won't go up.