What is a “BTB” kit?
The “BTB” stands for Big Throttle Body. The larger the throttle body is, the less restriction it causes. Less restriction equals more airflow equals more boost. Try to suck air through a normal soda straw, then one of the big ones from McDonalds. You’ll see. The BTB is worth about 10 hp at redline – the faster the engine and supercharger spin, the more benefit it gives.