Agree on torqueing the bolts, but thread locker should help keep things tight. If it gets that hot, I may have bigger issues than to bolts loosening.
From Loctite's site:
LoctiteŽ Threadlocker Red 271TM is designed for the permanent locking and sealing of threaded fasteners. The product cures when confined in the absence of air between close fitting metal surfaces. It protects threads from rust and corrosion and prevents loosening from shock and vibration. It is only removable once cured by heating up parts to 500°F (260°C).