Lol read the sentence again dude, he says he saw a drop in mpg. 
Pro_steve did some experimenting with economy maps, might be worth contacting: www.hdi-tuning.co.uk. I saw a 10% rise in my mpg from one of his economy maps, but i saw the same gain with his normal stage 1 map, so long as i didn't use the power anyway lol.
You know what, just look at my project thread lol, link in my sig down there VVV. Loads of ideas in there - longer gearbox from a 206 eco (rare as hens' teeth, unfortunately); lowering the car (genuinely helps); undertrays, full or partial; etc etc.
Pro_steve did some experimenting with economy maps, might be worth contacting: www.hdi-tuning.co.uk. I saw a 10% rise in my mpg from one of his economy maps, but i saw the same gain with his normal stage 1 map, so long as i didn't use the power anyway lol.
You know what, just look at my project thread lol, link in my sig down there VVV. Loads of ideas in there - longer gearbox from a 206 eco (rare as hens' teeth, unfortunately); lowering the car (genuinely helps); undertrays, full or partial; etc etc.