Ive never been really satisfied with the way the cooling system has performed and now that its warming up here (Phoenix) the engine temps seem to be creeping higher. Here is what I am working with: 67 Belvedere, 451, 10.5:1, Edelbrock heads, the block was cleaned three times during the machining process and a final cleaning before assembly so all the passages are clear, the 26" radiator was cleaned by a radiator shop prior to the new motor going in. I have ran a 7 blade flex fan and currently running a factory 7 blade clutch fan with a new Hayden clutch. The fan clutch is sitting 7/8" - 1" away from the radiator and using a factory shroud. 16 lb Chrysler radiator cap. The last time I drove it the temp was about 92 or so and going down the highway was running about 200 deg and then to 220 after getting off the freeway and pulling into the cruise in. I was running a Robertshaw 180 stat and have since replaced that with a Mr. Gasket high flow 180 stat with no real drop in temp. Distilled water and water wetter. The lower radiator hose has the spring inside so that should not be collapsing.

I also run a trans cooler to help with running a 9.5 torque converter. I do not think it is a lean issue with the carb or timing because it pulls way too hard and strong. Not sure what else to try at this point as I dont think I need to resort to electric fans and that sort of thing.