I have a diesel car and i want to max the horsepower but still keep the good fuel mileage, what should i improve or replace on the car?
The three most cost-effective mods that will improve mileage as well as give a decent boost in power are a cold-air intake, headers, and a high-flow mandrel-bent exhaust system. Another good mod, although it is a bit more expensive, is a piggyback programmer that you can usually plug right into the diagnostics port. If you get one, make sure that it can save multiple programs, e.g. one for high performance, one for cruising around town, and one for highway driving.
You need to shift your thinking away from horsepower with a diesel...it's all about torque now...it that's a good thing. I read an article in Grassroots Motorsports about a fellow with New Beetle TDI who had made some conservative modifications and was producing over 400 ft/lbs of torque in his car...and racing it. (article: http://grassrootsmotorsports.com/articles/your-mileage-may-vary/) I can't seem to find the magazine...but the seems to have the text under the title: Practical Performance: V8 Torque Meets Econobox Efficiency. Some good information to start with there. Good luck.
also, check out TDICLUB.COM
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