Snow Engine Project

[Tlm8kr]

Hello,
My next project is building a Snow engine but I would like to scale it up by 25%. Is increasing the scale of engine plans as easy as multiplying all dimensions by the same percentage? Something tells me that there's more to it. Will I run into trouble with the increased bore & stroke affecting the compression ratio? Are there other things that could affect the performance?

 

[mu38&Bg#]

Theoretically you'd be OK just scaling everything. However, if the engine uses any purchased parts like bearings, shafts, or screws, you'll have to accommodate stock sizes. Compression ratio scales with all the other dimensions.

 

[b.lindsey]

Welcome to the forum! As for scaling up, while most things can be multiplied by 1.25 just be aware that you may end up with some odd dimensions. For example scaling up a 1" bore results in 1.25"...no big problem there. Scaling up a 7/16" dimension (.4375) however will give you a somewhat non standard .5469" result...doable but not a standard stock size. I am thinking you would have to pay particular attention to things like seals where you may have to adjust the scale factor to achieve a more standard available size.

Bill

 

[Tlm8kr]

Guys,
Thanks for the help. I will try to post a few photos of the engine when I get started.

 

[T70MkIII]

Guys,
I will try to post a few photos of the engine when I get started.

Please do - this is an awesome looking engine, and one I hope to build soon.

 

[Rustkolector]

Should not be a problem scaling up 25%, but check out everything before you start. You are going to have to make a lot of "undersize or oversize" decisions regarding items that don't fall into nominal dimension sizes. Others are rumored to be building +25% Snow models, but I haven't seen one yet. One guy told me he is building a "Twin" tandem Snow. My aversion to upscaling this model would be the increased size and weight. A +25% size model will likely weigh about 65-70 lbs and be over 35" long. That's a lot to hall around to shows, but there is no reason it can't be done. At least you wouldn't have to work with all those little 0-80 screws.
Jeff

 

[Tlm8kr]

Thanks for all the input. I was going over some of the dimensions last night and I think a 25% increase will work for me.
I will need a 10 1/2" flywheel. Any suggestions on where to get one?

 

[gibbykart]

i am a member of a old engine club that has a 1100 HP twin snow engine and as i am a machinist i am going ot try to make a twin snow, any tips on the other side or would everything just be reversed?

 

[tonyr]

i am a member of a old engine club that has a 1100 HP twin snow engine and as i am a machinist i am going ot try to make a twin snow, any tips on the other side or would everything just be reversed?

Hello gibbykart

I have just come across your message.
I am also in the process of building a twin Snow engine.
I came to the same conclusion as yourself that the other side is just a mirror of the first side.
Have you made a start on the engine, if so I would be interested in your progress.

Tonyroscoe