Nail on the head cycho. The PAIR system is designed to burn off unburnt fuel in the exhaust by sending air into the exhaust. This can cause popping, or, in my case, flames. Removing it has no performance gain at all, you just lose a few ounces of emission controls. Oh, BTW, that's all it's there for, emissions. The greenies are at fault for this one.
2002 919 40,000 miles
"racing is life...everything else is just waiting"