Blown freeze plug

I have a hard time understanding incomplete sentences. Not making fun of you, but it's ME. I just recently found out I am dyslexic. Along with that, I sometimes see words that are not there and don't see some that are.

All that said, I reread your post several times and for the freeze plug, I would maybe go to a one size over size......OR you can switch over to a metric plug that's a tad larger. You can also drill the sides of the hole and pin the plug in. That's an old racer's trick. It works well.

As to the spike in temperature, what thermostat are you running? If you're running a factory 195, then I am calling that operation normal. Thermostat closed on startup, opens at the spike, then the engine cools after the thermostat opens. Just an internet guess.