What does PORTING mean? I've read you can port a supercharger, port a plenum, port heads....what is this porting?

 

porting is when you take say your heads to a machine shop and they use a cnc machine or a metal lathe and grind out some of the cylinder wall to make the opening bigger.

 

Porting like he said is increasing the size of the hole, to allow for more air to pass. Polishing is the removing of any rough edges inside the runners or w/e it is your Porting and Polishing to get the air to run smoother. Hence, a Port and Polish will increase both the volume of the air flowing through the intake/heads/supercharger, as well as smoothing out how that air flows.

 

Porting is generally done by hand, and it is the act of matching the dimensions of two connecting passges--most often in the intake tract. For instance, matching the outlet of a throttle body to the inlet of the plenum, the outlet of the plenum to the inlet of the intake manifold, or the outlets of the manifold to the intake ports on the head.[/align][/align]The goal is to provide a smooth transition from one component the next to minimize turbulence--sometimes in this process one or both opening are enlarged to enlarge the passages, sometimes the openings are just tapered to provide a smooth transition.[/align][/align]Polishing is, as stated above, the removals of casting lines and any other imperfections from the passageways and polishing same, sometimes to a mirror like finish.[/align][/align]

 

Uuggh...heads do not have cylinder walls and cylinder walls can be honed or bored/honed but not ported. Heads have ports, such the name porting, as it most commonly refers to enlarging the ports(runners) to speed the velocity of the intake charge and/or exhaust gasses. Just removing material to allow more flow is not always good as velocity is the key with flow so it's best left to the Pro's. As the other post said matching parts so there is a smooth transition is something that can be done at home with the tools and patience/time.
Remember an engine is an air pump, more/quicker in, more/quicker out the more power potential there is. devsredgtpo just clearing what you said as you combined a few operations into one piece that did not fit. Sure you have it correct but simply didn't say what you knew! Mark

 

so do u actully see gains of doing this
is it pricy. i have heard ppl doing it to the tb and plenum does it work

 

[/align][/align]In an otherwise unmodified engine there will be little to no gain, however as you improve the volumetric efficiency of an engine it is something to do to get every bit of power there is--by itself the gains are minimal...[/align][/align]

 

cliffyk
ok. little gains on stock motor but what if i change the cam? would it be benifical to do all that at the same time?

 

Say you had a 75mm TB and you ported it, would that mean you made it like 77-78mm or whatever??

to me it seems like porting a tb/plenum the gains would be minimal, but i bet i would see more if I ported my heads right?

 

they wouldnt open up the whole throttle body they would make opening of the plenum and the outlet of the tb match