I really wanted to try a buildable third-gen Camaro concept. I started looking directly at the IROC-Z styles and realized maybe a simple, plain-body non-IROC would be unique. The idea here is for a no-nonsense performance Camaro without big wings, ground effects, or vents all over the place - just wheels and stance to set the aggressive attitude. A few mods to the front bumper to clean it up and bright orange paint with a hockey stick-style stripe are all she needs. Wheels are large-diameter Minilite-style, similar to what old Trans Am race cars ran on in the late '60s and early '70s.
Engine choice is up to you, just keep it low profile so the hood can remain un-violated. You can still find these "Plain Jane" Camaros all over the country in decent shape and dirt-cheap. Their style alone gives them a great start as a killer street machine.