So I'm new and drive the antithesis of aerodynamics--an '06 SCION XB. I've been doing some general non-eco modding (interior and sound system), but want to do some stuff to improve fuel efficiency as well. I'm thinking about NGK iridium plugs, an afe air filter, and smoothies, probably caps b/c they're cheaper. Here's my question. Can I do baby moons or whatver they're called, where it's just the center cap on top of the steelies, or does it need to be the whole cap? For looks and price, I'd prefer the baby moons (I'm not going to use pizza pans), but ultimately I want to improve my mileage to lessen my impact, so I'll go with the full ones if that's what it takes.
Here's a pic of the center moon caps:
http://www.autoamenity.com/images/Nubs-MoonInst.jpg
Here's the full caps:
Smoothie Hubcaps 15 inch
and stainless without the lip:
http://images.google.com/imgres?imgu...%3Den%26um%3D1
Thanks for your input! Peace.