The thermocouples are inconel and measure upto 1100c but melt at 1250c. I chose 3mm dia ones. Although they read slower than say 1.5mm dia ones, they are less likely to break and that seems the STD automotive size.
They stick half way out into the manifold which I guess is about right.
My turbos already eaten a bolt, I just hope it doesn't eat these too..
