Photo etching parts- What is this for ??

Absolutely not..! Superglue is I'd say the prefered medium for PE/plastic. I've also used low-tack stuff such as Future and gloss varnish to 'glue' PE parts to delicate areas (for instance on windshields, because superglue cause 'frosting').

Domi

Okay.. I think I'll get my hands dirty for this. I've seen the picture from Scalemotorsport. and it's awesome..
superglue ? so I guess normal tamiya cement won't work ?

Butek, mostr PE sets are designed to improve plastic kits, so those are to be mixed up with the provided plastic parts. Use superglue, epoxy glue or even wood glue (for the final bits) to stick them on. There are a few full PE kits available nowadays, though even those do feature the odd plastic parts (such as the Eduard Strip Down biplanes series) or are meant to be used with existing chassis or tank hulls/tracks/wheels for instance.

Wow!! great stuff I'm gonna get one of these for my impreza rally.
thanks reggie and djmodels.
do I combine the plastics part with the photoetch ? or just use the photoetch ?

Reggie got it right. Manufacturing processes prevent the molding of very fine, thin parts. PE is a way to remedy this. However, things have gone very far, and many parts you'll find on a PE set are often too thin to be useable...

photoetch parts are small pieces of finely etched metal, designed to add detail that plastic cant provide. have a look at some at this link below

http://www.scalemotorsport.com/default.asp?photoetch

btw, butek, where are you from ?