Johnny Posted May 18, 2009 Report Share Posted May 18, 2009 I took the time to cut apart a scrap-head that I have, it got quite a beating before I was done The pictures are from the first cylinder. Quote Link to comment Share on other sites More sharing options...
Pugsley Posted May 18, 2009 Report Share Posted May 18, 2009 I took the time to cut apart a scrap-head that I have, it got quite a beating before I was done The pictures are from the first cylinder. Those are faily good size ports for a small engine, the contours are well blended with a minimum amount of steps in them or sharp turns or corners . Should be able to make pretty good power without porting them. Quote Link to comment Share on other sites More sharing options...
Johnny Posted May 18, 2009 Author Report Share Posted May 18, 2009 At first I'll probably just smooth out all the sharpe edges on the ports, just to get it running before the end of time. Later I was thinking something like this: Intake, raise the roof a bit, add J-B weld to the bottom, make the small radius smooth and as large as possible and smooth out all the sharpe edges. And look more deeply into getting the correct cross section area and mean velocities for the intended rpm. I think I have a basic understanding of how that works, but I need to study that a bit more. How does that sound? I haven't found much info about cross section area for exhaust yet so I'll probably just smooth it out as best I can. Mayby some of you guys have the expertise? Quote Link to comment Share on other sites More sharing options...
Pugsley Posted May 19, 2009 Report Share Posted May 19, 2009 At first I'll probably just smooth out all the sharpe edges on the ports, just to get it running before the end of time. Later I was thinking something like this: Intake, raise the roof a bit, add J-B weld to the bottom, make the small radius smooth and as large as possible and smooth out all the sharpe edges. And look more deeply into getting the correct cross section area and mean velocities for the intended rpm. I think I have a basic understanding of how that works, but I need to study that a bit more. How does that sound? I haven't found much info about cross section area for exhaust yet so I'll probably just smooth it out as best I can. Mayby some of you guys have the expertise? Worked on engines in my military days. There was always a theory that you didn't want the intake ports to be too smooth as a little rough helped with turbulence. Quote Link to comment Share on other sites More sharing options...
V-M Posted May 19, 2009 Report Share Posted May 19, 2009 Yes, Intake side some roughness is needed to have small surface turbulance to help better air mixture to fuel. Like sandblasting kind of surface is good. Exhoust side should be polished good. V-M Quote Link to comment Share on other sites More sharing options...
Johnny Posted May 19, 2009 Author Report Share Posted May 19, 2009 I ment the shape should be smooth, not the texture. Quote Link to comment Share on other sites More sharing options...
Pugsley Posted May 20, 2009 Report Share Posted May 20, 2009 I ment the shape should be smooth, not the texture. whoops, me bad. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.