Jay that's a cool tip... but what keeps you from creating it the way you want it the first time then just duplicating the finished product instead of duplicating it before you add all the loops?
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thanks man, I appreciate the comment. It's the first and only car I've made and it's still incomplete.

Do a wireframe render of your model. I came across a site with the instructions here: http://www.olivervisualfx.com/Optimized_Rendering.htm

Here are the instructions copied over (you need the...