What exactly is the difference in the different kind of porting to get?

First of all, I believe there are basically two kinds: bridgeporting and streetporting. Please correct me, because I'm probably wrong.

Other than the answer "bigger holes", what advantages are there for the "better" kinds of portings? (As in...how is Bridgeporting better than streetport... or is it?)

Any links would be helpful too.

 

Streetporting is any kind of porting which is limited to extending the stock ports. It allows somewhat better airflow, but the main source of power is the delayed closing of the intake port. This allows more air into the combustion chamber. This in turn creates more power. The downside compared to stock ports is that the power zone is shifted up higher. Therefor, the engine must be revved higher to achieve full power. Also, emmisions go out the window and fuel economy suffers.

Bridgeporting is similar to streetporting in that like streetporting, the intake ports are extended, but now a slit is cut next to the port which opens up the port sooner then before, while still allowing the corners seal to cross over a bridge of metal. (You have to see one to understand what I mean - try searchin) This shifts the power zone up even higher and substantially reduces low-rpm torque. Bridgeports get lousy gas mileage, have a rough idle and are really fast. J-ports and Monsterports are simply big bridgeports.

The other kind of porting is peripheral (sp) porting. The stock intake ports are filled and new ports are machined into the rotor housings, so they are on the periphery. Most power potential, but least drivability.

Hope this helps. Lots more info available in the archive or if you search.

Conway

 

Yes, that pretty much answers my question. And I will search in the archives as well.

 

Here is pics of a street port and Bridge Port from Pineappleracing website

 

Dam thats a BIG bridge...

http://www.mazdarotary.net/porting.htm

 

nice info. just got a bridge ported rx7

 

Red Bull gives you wings.

Bridgeport gives you wood

 

2003 thread .... nice

 

Lol