Hi Eric ,
Not so much why do builders choose to finish their engines all bright and shiny but more why do small engines look disproportionately shiny and bright relative to real engines .
This is mostly down to various scaling and real and perceived optical effects model v full size ..
These include :
The relative coarseness of finish on bright parts – especially things like con rods and flywheel rims
The relative matt / gloss levels of paint .
The different appearance of large areas of any chosen finish against small areas of same finish .
Viewing distance and viewing subtended angle .
Play of light and refections of parts and surrounding scenery .
That's a few first thoughts but several more effects are probably involved .
Regards ,
MikeW
Edited By MICHAEL WILLIAMS on 08/07/2013 13:20:36