So I built this 500 or so part armored personnel carrier, and while the vehicle on its own doesn't stress KSP out, I noticed something odd while testing the armor. I crashed a plane into it, overheating some of the armor near the back, and suddenly, the game slowed to an absolute crawl. It went away once the overheat did, leaving me with questions and no answers. Here's the link: https://kerbalx.com/Mycroft_33/Armored-Personnel-Carrier