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Hey guys, just wondering if someone can help me, have a new blitz blow off valve and when its fitted to my car exhaust backfires when shifting in midrange and also stalls when i boot it then back off. Runs fine and doesnt have any worries at all with standard valve on. The blitz is on the piping down to cooler which means i have put a blanking plate over origional mount and blocked lines. Might it be that the valve is not suited to the car or does it need to be dynoed or wat? only had my car bout 3 months so im pretty new to it all! any help would be appriciated!

cheers

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a simple search would tell you that the problem is the type of BOV

the stock BOV vents into a pipe that is plugged back into the intake just before the turbo.. so when you let off the accelerator the air is not lost, rather it is kept and re-used and the car is expecting this..

your BOV gets rid of the air, but the car isn't expecting this so (basically) starts to shit itself (your symptoms)

either put the stock BOV back on or get one that is the "recirculating" type or "plumb-back" type (i think GFB and turbosmart both make these types just to name a few)

sure, they won't make as loud of a "pppppsssssssssssssscccccccchhhhhhhhh" but they are still functional and audible..

cheers,

Warren.

I have a similar setup to you black_gtst where the bov is welded to the piping that goes to the intercooler and a blanking plate put in where the stock bov was.

I get exhaust pops now like you but the car doesn't stall.

You'll need to adjust your bov so the spring inside is tighter. My hks one has an adjustable nut that does it, it might be a similar thing on your Blitz

ha, yea bro, my car does the same. i have an Apexi BOV. back fires and sometimes it feels like its gonna stall afta i give it to her. i donno whats up wit it. but yea, i'm car is at the show now, so his gonna have a look at it. i'm gettin my FMIC and bigger fule pump and injectors put on :O

mad as, thanks heaps 4 that guys. Got a new idea with it, going to get a plate made up where the valve vents out so i can plumb it back. fingers crossed that will help the problem! This sites f*ken fantastic! Cheers!

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