The 110 Adventures.

[ImpulseRocket]

Decided to start on the easiest thing first and start cleaning up the head. This isn't complete, just started with the combustion chamber. Removed the coating which has a porous and rough texture and worked on cleaning it up with a set of scotch brite type rotary tool bits that go from 180 to 1000 grit. It also helped witih removing the sharp edges around the little pocket for the spark plug. I have some polishing pads on the way to finish it up, but honestly even this would be more than sufficient.

Before.

After.

Not really aiming for a perfect mirror finish, as much as that would be fun. The next step for me is to clean up the mating surface by decking it and also finishing it with a fine grit to ensure a good seal.

 

[Chainlube]

Decided to start on the easiest thing first and start cleaning up the head. This isn't complete, just started with the combustion chamber. Removed the coating which has a porous and rough texture and worked on cleaning it up with a set of scotch brite type rotary tool bits that go from 180 to 1000 grit. It also helped witih removing the sharp edges around the little pocket for the spark plug. I have some polishing pads on the way to finish it up, but honestly even this would be more than sufficient.

Before.

After.

Not really aiming for a perfect mirror finish, as much as that would be fun. The next step for me is to clean up the mating surface by decking it and also finishing it with a fine grit to ensure a good seal.

That's kinda weird, it doesn't have a defined squish band. How does the piston mate up to it?

 

[DieselTech]

I think I mentioned the cylinder head is of design. That's my opinion, I think they designed this head this way to be real low compression/big combustion chamber to keep wear & tear off of wrist pin bearing. Smolik makes a nice cylinder head for them.

 

[ImpulseRocket]

That's kinda weird, it doesn't have a defined squish band. How does the piston mate up to it?

The entire dome of the piston will fit within that chamber. Obviously not a perfect match by any means, but in order to get any compression at all the entire piston dome needs to protrude out of the top of the cylinder. It's definitely not ideal by any means.

 

[Chainlube]

The entire dome of the piston will fit within that chamber. Obviously not a perfect match by any means, but in order to get any compression at all the entire piston dome needs to protrude out of the top of the cylinder. It's definitely not ideal by any means.

That's quite the piston. Do you have a picture?

 

[DieselTech]

That's quite the piston. Do you have a picture?

Here is mine. I need to build it as well.

 

[ImpulseRocket]

I think I mentioned the cylinder head is of design. That's my opinion, I think they designed this head this way to be real low compression/big combustion chamber to keep wear & tear off of wrist pin bearing. Smolik makes a nice cylinder head for them.

It was definitely intended that way, but I think somebody forgot to tell them to stop. Nearly 3mm of "squish" at the tightest spot in that chamber is a lot too far past low compression. A nearly 1mm thick head gasket really doesn't help.

I don't think it is entirely without hope. I think it is perfectly possible to get a decent compression ratio out of this engine. At least good enough to get it to run worth a darn. The angle of the chamber sides is steeper than the domes curvature, so it will still force the mixture to the center and help with swirl. I just think that if your goal is a seriously high compression this head won't work out. I personally don't want a ton of compression on this. If I can get the gap down to .8 to 1mm I think this engine would be a perfect low octane runner.

That Smolik head is tempting though. Just wish they weren't sold out.

 

[DieselTech]

It was definitely intended that way, but I think somebody forgot to tell them to stop. Nearly 3mm of "squish" at the tightest spot in that chamber is a lot too far past low compression. A nearly 1mm thick head gasket really doesn't help.

I don't think it is entirely without hope. I think it is perfectly possible to get a decent compression ratio out of this engine. At least good enough to get it to run worth a darn. The angle of the chamber sides is steeper than the domes curvature, so it will still force the mixture to the center and help with swirl. I just think that if your goal is a seriously high compression this head won't work out. I personally don't want a ton of compression on this. If I can get the gap down to .8 to 1mm I think this engine would be a perfect low octane runner.

That Smolik head is tempting though. Just wish they weren't sold out.

When I talked to him he mentioned the cdh110 heads were made to order.

 

[ImpulseRocket]

That's quite the piston. Do you have a picture?

I don't have a picture at this time. There is nothing all that special about the piston, it's just a 52mm version of your standard domed piston most of these engines come with, but with a 12mm wrist pin. This is just the piston. https://www.amazon.com/dp/B09FF1GQML/ref=emc_b_5_t

 

[Chainlube]

Well, you know what they always say, there's no replacement for cubic inches.