HOW THE NUMBER OF PORTS AFFECTS AN ENGINES PERFORMANCE
07-15-2008, 08:00 PM
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HOW THE NUMBER OF PORTS AFFECTS AN ENGINES PERFORMANCE
I've been shopping around for a .21 marine engine as an upgrade. On the low end of the spectrum, the .21 Go engine competition model has 3 ports ($131.00) whereas the .21 Go engine Pro has 5 ports (263.00) and the Rossi Piranha has 7 ports (383.00). Obviously the number of ports is one of the factors that affects the price. What do they do? Why is more better (or is it)?
07-15-2008, 11:17 PM
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RE: HOW THE NUMBER OF PORTS AFFECTS AN ENGINES PERFORMANCE
More is better to a point. More ports means more fuel into the cylider faster and controls the fuel/air swirl pattern which CAN translate to more torque and RPM. At the same time, more ports can mean a weaker sleave since the are normally arranged in a line. Port size and location is equally as important as number of ports, so IF you can find the engine specs, look at the torque specs and ignore the RPM and HP ratings since these are normally not anything more than a sales ploy
07-16-2008, 06:33 AM
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RE: HOW THE NUMBER OF PORTS AFFECTS AN ENGINES PERFORMANCE
Glenn Quarles made a comment about the nova rossi motors that kind of stuck in my head. He was looking at having a cheaper version of the motor made with less ports. If I remember right, the comment he made was that some of the extra ports were just for cooling the piston, which we as boaters don't really need (I guess that is in comparison to car guys). So I guess that more ports are better to a point...then it just starts costing more money for doing things we don't need...
Sean
Sean
