is a blow off valve a necessity when you have a super charged or turbo charged engine? also a friend off mine says they are illegal in CT and i argued saying they aren't. can anyone assist me?

They are necessary when running like 6 psi or more to keep from damaging the compressor.

You can use a BPV or a BOV. BOVs are not illegal if the car originally came with one (ala 1G DSM). But if the car is a stock turbo car with a bypass valve and you convert to BOV, it is illegal because the car is dumping unmetered air which makes the car fart more emissions.

thanks for clearing things up for me

For a supercharged car though you should be running a BPV since the valve is going to be post MAF.

Unless his supercharger is blow thru or standalone.

Unless his supercharger is blow thru or standalone.


That sir is a true statement.