Thanks for the tips. As I said I made the ports purely based on pictures as I dont have knowledge of the different effects of port design. I’ll try to improve the intake turn. The intake is slightly larger than the exhaust port with the intake being 2" and the exhaust being 1.75".
As for dummy engines thats not something I plan on doing. I was only planning on making the 3d printed models. I dont even know what I would do to have a dummy engine made.
Alright i redesigned the intake port and made the corner a bit wider so what do you think of it now @Darkshine5 ?
Correct me if I’m wrong… but I think the problem is the bottom curve of the intake tract. It may actually be beneficial to reduce the width of the upper tract in order to gain a smaller radius turn on the bottom. The reason I say that is because at high velocity the boundary layer will detach from the bottom wall of the tract and conflict with the airflow above it.
That said… this isn’t a real engine, and so it doesn’t really matter. Fun project you have here 
Fun little off-topic fact… we’ve been attempting to speed up intake air velocity since the dawn of automotive history. Now the highest performance engines are actually slowing it down, because certain race engines have attained transonic airflow, and those shockwaves and boundary layer separation in the intake tract wreak havoc on flow, so now they’re slowing flow down to strictly subsonic speeds. I have to wonder if they’ll ever perfect supersonic airflow in an engine. Once it passes the transonic stage, flow theoretically could be manageable, but I think that it will be impossible to get to that point in the first place because flow plummets when the transonic stage is reached.
Do you mean the crease where the curve and the funnel sections join together? If so that’s only sharp because I don’t know how to make it smooth. The only way I know how is to make it so the size of the port remains the same the whole way.
I assumed you would file away that crease on the model itself. I am talking about the angle of the bend I outlined below.
From what I understand about aerodynamic flow… that port will actually flow worse at high velocity compared to the smaller exhaust port because that steep angle would lead to tumble and boundary layer separation. I could be wrong though.
Should I remove the slight straight section under the curve and make it so its the curve that connects to the cylinder? I remember hearing that you want the straightest flow into the engine so doing that would also reduce flow in a way.
This is likely the most effective port shape for an engine with vertical valves, without going too crazy.
The cross-section is bean-shaped.
You also want the port’s cross-section or diameter to remain constant along it’s whole length; even if the shape of the tract changes; basically exactly the same as Area Ruling for aircraft.
That widening bell mouth would likely create turbulent flow.
I think I see what you were doing though, that performance port;
looks like it gets wider and has a bell mouth, and you were taking inspiration from that… but in reality it likely just changes from a round to a more square cross-section. The change in geometry is an attempt to influence more positive flow characteristics; such as minimizing fuel-air separation. I can’t say too much on specific shapes though because I have a lot more to learn.
Hmmm the bean shaped port entry is a new one to me. What would be the benefits of this over a more oval shaped entry? Would not this unique shape hinder the tumble effect of incoming air?
Does this look better?
are you going for DAOHC??
Yup. It’s the simplest to design and also the easiest to put together for the model.
@Darkshine5 I assume it is shaped that way to help direct flow around the valve stem instead of having it hit the stem at high velocity causing turbulence.
Not sure about the effect on tumble here to be honest.
Take a look at a Nissan RB’s ports if you want to see something even more interesting than a bean;
@rcracer11m Yes, that looks a lot better.
its awesome
Heres the head all put together so far. A few changes will need to be made but this is the general idea.
If you can, perspective view please? Parallel projection hurts my brain
I’ll try too remember tomorrow at school, don’t have access to this while im home.
Okay, don’t worry about it if it’s a chore 
don’t waste your time
mate love your work this is very cool.
A question what kind of plastics can you use on this machine? would it be possible to make an intake manifold that could support fuel?
Our printer can only print ABS plastic.
but if you have a little bit of money to spare. why not get a can of teflon spray and paint most of the friction inducing parts. after it dried, a bit spray of wd-40 will go even further.
