1200hp 12 valve engine fore sale, 0 miles!

yes, i did cc them. they are 10cc's. even thought the surface gets covered with carbon, it still will reflect the heat energy. the heat energy will conduct through the carbon then be reflected by the polished surface underneath. there are companies that coat pistons and such to reflect heat. they get coated with carbon too. yet they still have proven that the heat gets reflected, even through the carbon, same concept here... ;)
 
rgsmith70 said:
yes, i did cc them. they are 10cc's. even thought the surface gets covered with carbon, it still will reflect the heat energy. the heat energy will conduct through the carbon then be reflected by the polished surface underneath. there are companies that coat pistons and such to reflect heat. they get coated with carbon too. yet they still have proven that the heat gets reflected, even through the carbon, same concept here... ;)
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That's good on the measurements. I wouldn't worry at all about them being slightly uneven (not perfectly smooth) then.

On the heat transfer stuff, my train of thought is there are three ways to transfer heat; conduction, convection, and radiation. Conduction is physical contact between solids and will always transfer heat the fastest out of the three ways. Convection is the transfer via a liquid/gas. This is dependent on flow rate and wall roughness typically, and buoyancy is a factor (the whole heat rises thing, but not as much with quick events). Then there is Radiation, which would be the transfer of heat via emissivity (~light rays).
Usually polishing (strictly talking heat, nor polishing runners, or connecting rods) is done to reflect radiation since radiation is light based, the more reflective the surface, the less heat is absorbed. This is also why laser cutting shiny stuff is a pain. Convectively, the rougher the surface, the more heat transfer because the rough surface breaks up the boundary layer near the wall and slightly increases the surface area (think micro-fins). So I’d think it would help in that aspect.
There’s no conduction in cylinder regarding the ignition. My thoughts being; the polished surface gets coated by a rougher, non-reflective layer of carbon, and now absorbs some heat. Then conducts it through the layer of polished surface as if it weren’t there. The only advantage I could see at this point would be that you’d still have a smoother surface than a standard carbon coated head, and convectivity would be down.
So… after thinking through it all. I can see an advantage. I’m just not sure if you’d be able to measure a difference in an A to B test.



Also, sorry to get off topic on your for sale thread. I like seeing people trying different things and discussing them.
 
i don't mind off topic, cause it's really not, it could answer some people's questions about the work here. how much light energy is produced during the combustion process?? ;) lots of photons there, they may get through the carbon layer but not the polished surface underneath. don't forget to consider that. just cause you cant see the light, doesn't mean it is not there. it also, as you mentioned about rough surface, reduces areas to begin melt down. especially on the piston.. :-0
 
rgsmith70 said:
i don't mind off topic, cause it's really not, it could answer some people's questions about the work here. how much light energy is produced during the combustion process?? ;) lots of photons there, they may get through the carbon layer but not the polished surface underneath. don't forget to consider that. just cause you cant see the light, doesn't mean it is not there. it also, as you mentioned about rough surface, reduces areas to begin melt down. especially on the piston.. :-0
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I'm definitely no heat transfer or thermal dynamics expert. I know just enough to be dangerous. However, I'm pretty sure the black 'dust/crust' the carbon leaves behind is extremely good at capturing thermal radiation. Just like if you left a mirror in the sun vs a black blanket. The black blanket would get hot. Now if you left a black blanket on a mirror in the sun, the blanket would catch the thermal radiation, and then transfer it into the mirror through conduction, eccentrically leaving the mirror useless as a radiation reflecting device.

I could be wrong, just my train of though!
 
take an acetylene torch, and two hex bolts. polish one hex bolts top like a mirror. set the torch to the nice blue flame. try cutting both bolt heads from the middle of the head, watch what happens... ;) all doubt will be answered! the polished one takes waaay longer to cut, ask me how i know!?? lol you can even use the acetylene with no oxygen for a few seconds on an other polished head. it will coat it with carbon. then try to cut it again and compare it to the un polished bolt head again. wich takes longest to cut... the polished one does!! the un polished one cuts super fast the polished one takes a long time. even if coated with carbon... again.. ask me how i know..lol try it.. u will see. and that is real world conditions as compared to a combustion chamber.. at least waay closer to one then a blanket in the sun. take a polished METAL mirror and a blanket, hit it with that torch and see what happenes there too. the chamber is iron not glass, thats y i mention it that way... have fun experimenting...
 
here is a before pic of the bowls
 

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Fair enough. Like I said, I'm no expert. That was just my thought process.

Maybe the next time my head is off, I'll try polishing everything a bit ;-)
 
don't be afraid to through out offers, worst i can say is no..lol just be reasonable!!
 
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