At 450 degrees your coolant WILL be boiling out the overflow and you WILL have a cracked head and you’d probably already have burst the rubber coolant lines. Whatever you are using to check that temp is wrong.
I would bet you aren’t overheating...
I didn’t think so either, I’ll try and get a pic next time. Fan is spinning the right way, and yes when it’s topped off it will dump out fluid for a while. Doesn’t sound like it’s boiling though.
It can’t be 450*.
All good suggestions (above).
The dollar bill trick (put a dollar bill on the front of the radiator to prove the fan is sucking) is a good test.
Does it puke out fluid when you stop with a full radiator? Does it make boiling...