I run 50/50 af/h20 with hi-ouput water pump, a 10" pusher (always on), and a 16" puller electric (thermostaticially controled) on my 34 (350 ci/350hp) and it normally runs in warm weather at about 200. No fancy radiator, aluminum or otherwise, not even a big name unit like Walker or Griffin, etc., just an old radiator with trans cooler in the bottom. I can sit (had to recently) and idle for an hour and it goes no higher than 210. Only shroud is that which is build around the puller, not a full coverage shroud. So far for the past 17 years very few water related problems. Hope it stays that way.