Originally Posted by michiganmaveric
I believe that turbo's do help in the gas milage department, but it would take years and years to recoupe the $3,000-$4,000 cost of modifing your engine.
I believe you are thinking Supercharger. Most guys the run SC'd Hondas see 1-2mpg better mileage due to the fact that you have more power to get you going and there isnt so much load on the motor.
Personally, I lost about 2-3mpg city driving and 3-4mpg highway driving after turbocharging my Honda. And that was with a fully programmable ECU and custom tuning to lean out the partial throttle cruising. I don't see that being any different with any sort of chassis, but real world results speak louder than assumptions.