http://ecomodder.com/forum/showthrea...omy-12895.html
A similar question with respect to 'Restriction' was posed in the above thread. The theory there was that reducing pumping losses would improve efficiency. But then 'what kind of car' is probably more relevant.
I do know someone else with an older year pulsar and they've gone with a CAI in front of the car (big 50mm tubing). The engine is a 1.6L and they get near 600kM from a tank (not a good benchmark, but that got me thinking that some performance mods could be for fuel economy too).