i will say this. at a local dirt track the "new" late models have all the best aero noses and engine tech gained from years of cut and try. just a few months ago , a driver cut a lap at 16.118 ... the track was totally re-clayed and in the best shape in over 50 years. back up [37 years] to 1984 .. i have a news paper article stating a driver set a new track record of 16.112 at the same track!.............. 4/10s mile banked and fast track. so much for all the new improvements to the track and the new tech advances on aero, chassis and engines. they even have $2,000.00 [each] shocks ! get the basics for your class and learn how to set up -your- car.... now if you run Daytona , or super hi speed tracks add aero to your basics list.. master the basics first. dont over think it. you will find that in its self is a huge task......