[silverfdturbo6port]

I've used bags and wrap n street machines for many many years with no issues. Even with drag racing, autocross and numerous 180+mph pulls on 100* days I've never seen them "BDC" nor myself turn into a "KUUNT" but those are not harsh conditions like a race car as stated by Peter.
But for a dedicated "Race" car I will guarantee you will see the effects like in the OP.
But for daily driving/street use and you want to keep the bay temps down then Bags, wrap, shielding, heat coatings all work great.