Post this question on the Hokey Ass Message Board and you'll probley get an answer. http://www.jalopyjournal.com/ubbthreads/postlist.php?Cat=&Board=UBB1
Don't know if ya kicked this over to the main board or not but, your running 185 and your worried? Most folks with rocket mills dream of running that cool when it's 91 outside. That's perfect. If you start to hit 200-210 then it's time to worry. It sounds to me like you have a cooling system that is working great.
yes sounds good to me.i run a 160 termostat in my 56 and it runs 160 in cooler weather,and 185 in 90 deg weather.
i was wondering the same thing about my nailhead....it's been hot lately. I just had it rebuilt and flushed my system out. Here's something that's helped me run cooler; a product called "Water Wetter" made by Redline oil. It removes the oxy. out of the water and coolant and helps with heat transfer. The stuff works GREAT and I haven't even come close to overheating since i poured a quart of that stuff down the radiator. Later-John
Check your local speed shops and the like, they should have it in stock and if they don't, should easily be able to order it for you. I can throw a link to a website of a shop here in Houston that carries if you can't find it where you are.