BOV GOOD/ BAD

HI ALL I'V READ THAT THERE ARE SOME ISUES WITH A BLOW OFF VALVE (LOOKING TO GET HKS ONE FOR MY SONS 2003 GTI 1.8T) X-MAS. BUT I'V YET TO SEE ANYTHING ON HOW TO CORRECT THE PROBLEM OR IF YOU CAN'T GET AROUND THE M.A.S. ISUE. IF SOMEONE HAS ANY INFO OR A GOOD SERCH ENGIN TO TRY I WOULD REALY APRICIATE IT.

THANKS
TACKERDOWN[/quote]

A BOV and a DV more or less the same, and perform the same function. The difference in terminology is pretty much meaningless. Where people get their undies in a bundle and/or burned is the issue about venting to atmosphere or not.
With a closed, MAF-based system (such as my current motor, a 1.8 litre turbocharged Audi), venting to atmosphere will cause the motor to run rich

The ECU meters incoming air via the MAF, and using inputs from the MAF, TPS, MAP (if so equipped), RPM, O2 sensor(s) and who knows what else determines how long to fire the injectors. If any of that metered volume of air is vented to atmosphere, the ECU has no idea that it's lost some air and will fire the injectors long enough to match the volume or pre-metered air. Result? Rich condition.

The charge in the IC plumbing can travel well in excess of 100 mph, and when the throttle plate closes the charge has nowhere to go. A shockwave can bounce off of the throttle plate and travel back through the IC plumbing to the compressor, and if the impact is great enough can stall the compressor, or perhaps even spin it backwards. Which is 'a bad thing' as far as the health of your turbocharger goes. The wheels are spinning anywhere between 100k and 200k RPM. From 100k to 0 rpm in an instant? No thanks.

The BOVs open when presented with some specific measure of vacuum. Vacuum is produced immediately in the intake manifold when the throttle plate shuts, so as soon as the BOV "sees" whatever level of vacuum is required, (say 10 inches of mercury, for example) it opens and some of the compressed charge is vented out of the IC plumbing and back into the intake stream - between the MAF and the compressor. This venting is what protects the turbocharger.

So - use a valve which recirculates the vented charge, unless you've done a speed density conversion or are using a blow-through MAF, which sits in the IC plumbing, somewhere between the compressor and the throttle body. A blow through MAF is most likely in the IC plumbing just before the TB.

i am wondering the same thing! i want to upgrade my blow off valve and i am looking for a kit or a better bloe off valve that well work in the stock pipe any help well be nice!
thanks!