Having small intakes and outlets only works when the car is moving. You can wrap the heat components all you want but the heat still have to go somewhere, I meant currently everything down there hot is exposed but we can still feel the heat through the console box so sealing everything up will be just masking a problem. Then we have to worry about how the heat would affect the cat and stuff. Furthermore we still don't know how to design a good heat dissipation undertray without f**king up aerodynamics.

 

if you wrap the exhaust components the heat will come out the pipe more instead of radiate outwards from the body of the exhaust, the exhaust would be my main concern as far as heat goes, we know it get really hot. as far as the trans goes I doubt it gets hot enough to damage anything like the exhaust would.