nitrosaurus

what does this do and can it be used for on road?

mckrooz

iTrader: (8)

I've heard the gains are minimal. You probably won't even notice a difference. Not worth it IMO because you gotta drill a hole in your engine case

Lythion

It increases the plenum volume between the crank port and the carb. The volume is supposed to absorb the pulse of air that is bounced back towards the carb when the crank port shuts. This pulse can cause the fuel air mix to pass through the carb venturi again causing a double rich condition.

The consensus is that it does not make enough of a difference to warrant drilling up your motor.