good T stat temp for motor break in

I use a restrictor washer and straight water, with the box-fan on stand-by. Ive had brand new stats stick on me. What a scramble! Its not so bad when it happens and the customer isnt around to witness it.But it sure doesnt look professional when he does witness it.Customers tend to panic at every little thing, and then the questions start. And the doubts. And fears about the future. And you cant really blame them. Theyre the ones with the money on the line. When everything goes right, they tell their friends, who tell their friends, etc. I leave the water in there, with an additive pkg, til at least the tune is getting close, and the engine has shown itself to not be prone to overheating.Sometimes hours, sometimes days. In mine I didnt run antifreeze for years.Not that it wanted to overheat.But after the 205/210*stat went in I felt that straight water was prudent.It makes pretty good power at that temp with 87E10.As we aged together(the engine and I), I eventually put antifreeze in her.Now shes like a middle-aged wife, maybe a little rough around the edges, but if you prod her a bit, still has a bit of go to her.lol
FWIW, unless you have a really really big cam and electric fans, a properly tuned engine and cooling system,will be very hard to overheat.