Neat articles on DIY aerodynamics & other improvements.

[Improbcat]

I've been poking through the archives of the autospeed.com website's DIY section and have come across a few articles that might be useful to people making mods to their cars for fuel efficiency.

Modifying Under-Car Airflow, Part 1 & Part 2
Silencing Wiper Wind Noise (not strictly FI improvement, but has good info on prototyping, tuft testing & working with ABS sheet)
The 5 Cent Modification (using a resistor or adjustable pot to fool an engine into running richer or leaner)
Trialling a Rear Undertray (as someone who's rear undertray also underperformed I can extra appreciate this one)
Don't Bother Changing the Factory Filter (why high performance air filters are a waste of money)
Aero Testing - Part 1, Part 2 & Part 3 (how to do wool tuft testing & what the results mean)