anyone out there running some sort of blow off valve? i know when my L shifts at full throttle it makes this horrible whoopie cushion sound that annoys the crap out of me. anyone know if some sort of low off valve could coincide with our engines???

ps. i sold the bimmer so the lightning stays

 

That might be the belt slipping.

 

anything you can do to know for sure if it is the belt? it sounds like the noise is coming form the passenger side. should a stock truck be chirping 2nd?

 

Blow-off valves are typically only used on cars that have either a turbo or on centrifugal-type superchargers. This prevents backwards pressure from putting strain on the bearings and possibly damaging the scrolls. The whoopie cushion noise that you hear is the 'infamous' 1-2 fart. Ford saw fit to program the trucks to cut spark or fuel (can't remember which at this point) during the 1-2 shift to reduce the amount of torque the transmission was subjected to. I'm assuming you don't have a chip in your truck...most vendors automatically remove this feature in their chip programs. Install a chip and you truck's case of gas goes away. A stock truck will never chirp second for the reason stated above.

Dan

 

Believe me you ll know an aftermarket blow off valve when you hear one.

ITs the second best sound to our Supercharger Whine.
(Or as someone called it a WW2 bomb siren)

 

alright thanks. i know what the BOV sounds like. didnt know if they made one for our trucks for aftermarket.