Dynomax v mufflers (with valve)

[SNOWBIRD]

Has anybody tried these mufflers on our turbo cars ,i am afraid that 600 hp street cars will damage the valve and spring OPINIONS PLEASE ,,,O and are they silent when cruising ,THANKS

 

[cruzn57]

I cannot speak for valve type

but have the orig dyno max type, LOVE EM !!!
no drone, semi quiet at idle, throaty note under accell,
this is on my 350 hp street car,