Smooth vs. rough surfaces
Smooth vs. rough surfaces
I have heard both sides of the argument. And most people bring up vaild points to their sides.
If your intake pipe, TB, and intake manifold were completely deburred and polished smooth or deburred and the surface is left rough, which choice would yield a higher flow?
To throw a curveball in the mix. Would a dimpled pattern (similar to that on a golf ball) yield a higher flow?
I am curious to hear your thoughts.
If your intake pipe, TB, and intake manifold were completely deburred and polished smooth or deburred and the surface is left rough, which choice would yield a higher flow?
To throw a curveball in the mix. Would a dimpled pattern (similar to that on a golf ball) yield a higher flow?
I am curious to hear your thoughts.
If it were me, on a modern engine, I would prefer a smooth surface. Considering the fuel is added a relatively short distance from the valve, with a good injector that atomizes well, I don't think the surface needs to be as rough as on a carbureted V8, where the fuel and air have to stay mixed all the way down the intake runners and into the ports. But that's just from what I've heard in the past and what makes sense in my head. There are other people smarter than me that could probably add some more and go into your dimple idea.
You want the intake pipe, throttle body and intake manifold to be as smooth as possible with no ridges or lips which could cause turbulence and restrict/reduce absolute flow.
Also the manifold to head needs to be matched for the same reason, to reduce turbulence.
Now, after the injectors is a different matter, you want the surface of the intake port to be slightly rough for two reasons. Firstly, to help stop the atomized fuel from consensing/pooling on the port walls.
Secondly to produce very slight turbulence in the boundry layer to help keep the fuel/air mixture fully atomized.
Also the manifold to head needs to be matched for the same reason, to reduce turbulence.
Now, after the injectors is a different matter, you want the surface of the intake port to be slightly rough for two reasons. Firstly, to help stop the atomized fuel from consensing/pooling on the port walls.
Secondly to produce very slight turbulence in the boundry layer to help keep the fuel/air mixture fully atomized.
Clive has it rt....smooth looks nice...dimpled is functional and helps with atomization of the fuel.. Your original question was regarding air flow...does this mean increased speed or volume? Speed make power sooner...volume will make power up top... Bottom line, buy some grinders grease...and the right porting tools...port match and smooth where needed...dont try and grind away a big hole or your air speed will decrease and you lose power...plently of books on porting if you want more..
Clive has it rt....smooth looks nice...dimpled is functional and helps with atomization of the fuel.. Your original question was regarding air flow...does this mean increased speed or volume? Speed make power sooner...volume will make power up top... Bottom line, buy some grinders grease...and the right porting tools...port match and smooth where needed...dont try and grind away a big hole or your air speed will decrease and you lose power...plently of books on porting if you want more..
