First engine, material choices

[Jkrych]

finally going forward with an engine build. i'd like to get at least moderate performance, but i'm going to build a test platform prototype, which brings me to my question:
Ive decided on a steel liner, aluminum piston and cast iron rings. I know this is more difficult than say a steel liner CI piston, but i'm confident in my abilities to maintain dimensions. however i have a few choices of steel and i'm not sure which one would give good results. with a CI ring, 12l14 is out for a liner, so i was going to use 1144 or some chrome moly tubing- honed circular and then cross hatched. i have some 1215 steel in the right diameter for the crankshaft, but are "easy machining" steels suitable for a crankshaft? i was going to use a pressed in pin and a bush on the con rod big end. my alternatives are some 1018 and 1144. also, i should assume low carbon steel is not suitable as a liner material?

 

[Cogsy]

12L14 is a great liner material for use with CI rings - just look at Steve Huck's engines. Personally, I'd be using 12L14 for the liner and 1144 Stressproof (stressproof is important) for the crank and turning it in one piece.

 

[Jkrych]

12L14 as a liner with moderate performance goals? im planning on sport running the engine

 

[Cogsy]

What do you anticipate the problem to be? It machines well and runs well with CI as far as I know. Steve's V8 and V4 must have many hundreds of hours of running and haven't had any issues. I think George Britnell may use the same configuration but I'm not 100% sure.

 

[Jkrych]

maybe my amateur status with metallurgy has me confused, but my logic is telling me a material that is easy to machine would also wear away faster than a material that is more "difficult" to machine.

 

[Cogsy]

There is a lot more to it than ease of machining, or even hardness. Cast iron and bronze for example, they're both easy to machine and have fantastic wear/bearing properties. It's more about properly matching pairs of materials for the best characteristics rather than individual characteristics of each material. To take it to an extreme as an example, running a hardened needle roller bearing on a non-hardened shaft, the assembly will fail in no time at all because of the differences in characteristics of the materials. Put the same non-hardened shaft in a bronze bush and it'll run for years (properly lubricated of course) without appreciable wear.

 

[natalefr]

For the first engine, follow the instructions of the person who carried out the project and you will have a functioning engine, then with experience, you will be able to make modifications, usually before running, you will learn to walk

 

[goldstar31]

Perfidious Albion?
N

 

[natalefr]

I have already built 3 engines and I start the Hupshur Twin, I think that before starting to experiment with different materials, it is necessary to have a good experience and to be encouraged by the success of the previous constructions.
For example, in the Upshur that I built, I had a carburetion problem, the engines remained on for a maximum of 2 minutes, I discovered that the intake line was very hot, I spoke with a friend more experienced than me, we understood that the fuel evaporated before being sucked, I extended the intake duct and now the engine stays longer running. Start a motor by changing materials and if that does not work, becomes a difficult puzzle to solve and discourage the enthusiast
It's my humble opinion

 

[WOB]

12L14 is a great liner material for use with CI rings - just look at Steve Huck's engines. Personally, I'd be using 12L14 for the liner and 1144 Stressproof (stressproof is important) for the crank and turning it in one piece.

Excellent suggestion.

WOB

 

[Jkrych]

Thanks for the insight.