Backpressure question

[bvav22]

i recently got a new catback exhuast with a y pipe into dual tailpipes, with cherry bombs to muffle. i want to delete my cats but i am afriad more reduction in backpressure will hurt me? is it true that backpressure burning the valves is an old wives tale? cuase i alreayd have noticed my temp guages will go hotter then it used to if i am not driving fast enough to get alot of wind under it.

 

[Stinger]

Wives tail...