so i was checking out youtube and saw soem rx7s bridgeported. what exactly is that? it has a pretty nice sound in my opinion.

 

Bridgeporting is cutting another port on the outer edge of the intake port, against (and sometimes into) the rotor housing. This creates two ports where one port once was, with a small bridge of metal between them to support the corner/side seals. The bridge looks like an eyebrow on the main port.

Bridgeporting allows a lot more flow in the high end, but creates a lot of overlap between intake and exhaust. This can have negative effects on the low end and will dramatically increase your fuel consumption. However the overlap creates slight misfires which create very high combustion pressures, which will spool a turbo in the low end like nothing else.