As long as the coolant stays liquid, and inside the system, you're probably OK to 220 or so. A minimum of a 7-lb. cap should work, and 12 lbs. or more will give an extra safety margin IF you've got a tubular radiator. The old honeycomb design core won't stand that kind of pressure. If you fit a shroud, be sure it stops halfway over the fan blades- - - - -don't totally enclose the blade, or you'll end up moving less air, not more.
Jerry

Last edited by Hotrod Lincoln; 07/02/2008 3:15 PM.
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