A Polymer or epoxy metal? that will work on engines.

[Seafury007]

Hello,
It is my understanding that the flow off the fuel/air mix thru an engine is a factor in its output. A smooth low turbulent airflow thru the engine would increase its performance. I have some competition engines such as say the earlier K&B 3.5 front intake engines. On these engines the crankshaft bore from the piston area ends to a flat in the venturi opening area. Also the majority have the case port opening a bit higher than the sleeve. I am looking for a material that could be used to fill in these "Dead" or "Drag" areas on the fuel/air flow mix thru the engine.It needs to be a material that will bond to the steel shaft and the cast case well and can handle heat due to the area next to the cylinder at the ports.
Any suggestions or "Known" to work materials appreciated. I have a quick drawing drawn up of the mod I plan to do on the shaft if anyone is interested.
Rob