2020 revealed issues with excess heat. Addressing those will require both heat hardening of some of the susceptible components, and reducing temperatures in critical areas.
Addressing hardening first, both the brake mid flex hoses covers and cover on the LH parking brake cable suffered from heat damage.
A quick test with a thermocouple and a thermostatically controlled heat gun showed that both the brake hose outer cover and the end boots how signs of degradation at 150°C. Techna-Quip will supply brake hoses with a fiberglass heat shield on request. This shield also has a metalized reflective outer layer to reflect radiant heat. These look promising. To address the parking brake cable I installed a fire-sleeve cover in the affected area. While this lacks a reflective layer, it provides substantial insulation.
My earlier attempt to increase the stiffness of my exhaust hangers to reduce the sway space it occupies was not successful. The urethane hangers were stiffer (at room temperature) but failed by melting.
The OE rubber mounts seem to survive the heat environment fine, so I modified a set by filling the inner cavity space with RTV high temperature silicone. Regular silicone can only be applied in ¼” thick layers as it cures in response to air and humidity. Beyond ¼” and the material will never cure down deep, so multiple layers and multiple days were required to fully fill the cavity with silicone. A 2-component activator-curing silicone would have been a nicer solution, allowing me to fill the cavity in 1 shot, but I didn’t have any of the stuff.
A quick test of the stiffness of a new OE hanger and a modified hanger to be approximate 4 times stiffer. I did this by hanging 5-lb and 25-lb weights vertically and measuring the pin-to-pin distance with a caliper. The added stiffness makes them a bit harder to install, but I am very happy with how firmly the exhaust is now restrained.
Temperature reduction will be the subject of another post.