[aerohead]

I'm unclear with your mention of "splitter",can you help me out there? Personally,I'd leave the mirrors alone.The Insight has a frightening blindspot at the rear,and I think you need all the outward vision you can get.Safety first! With respect to the grille block,since you have a very expensive electronics package aboard that car,you must be much more careful than those of us burning only dinosaurs for motion.If you do the block,start small,monitor temps religiously,and work your way up incrementally to more blockage.The Insight is certainly a compromise between an extreme-performance vehicle and a limited mass-production, profit producer,however,I do believe HONDA has invested a lot of wind-tunnel time on the body of the car.The upshot is that the fore-body is very clean,the frontal area hits about where your head is,and then the body begins it's teardrop-taper for the duration of the body length,yielding the Cd0.25,which is great! The downside is,that there's very little to be gained by modifying the front of the car.If you'll look back in recent history,you'll find that,for virtually all car companies,setting out to break records,they went to the back of the car to do it.Whether the Chrysler Airflow"boattail",GM Oldsmobile Aerotech "Longtail",GM Sunraycer"Pumpkin-seed",GM Saturn Impact/EV-1/EV-2,boattailed LSR,Mercedes C-111, Volkswagon' 145-mpg Diesel,Porsche 917 long-tail,Cadilac"le Monster",etc.,they all turn to the wake of the car for added performance,and I'm afraid your facing the same challenge if you want to see measurable performance increases.Should you follow basjoos lead,you should end up in 90-mpg territory,while out on the open road.Not shabby by todays standards.Put the whole rig up on railroad tracks and your looking at 105-mpg.