Thanks for posting this JCR, the place you have fitted the pump is very elegant. I have always thought that placing it by the rad was a very difficult thing to do. Also, removing the water pump etc must free up some space at the front of the engine too. If you have time, I would appreciate some pics of the engine/blanking plate area too. There can be no doubt that reducing the hot stop temps as you have must be a very good way to preserve everything under the bonnet, including gasket and seal lives, quite regardless of whether steam pockets form or not. I look forward to the under bonnet figures once the summer appears.

If I get it right, your pump will pulse always, until the water temp rises a bit when it runs the pump continuously, and then if the temp rises a bit more a bit more it activates the fans. What temperatures, please, do you make the transitions at?

Thanks again for the myth-busting and very useful measurements
Greg