Have a look at these.
http://www.ebay.co.uk/itm/3312254370...84.m1423.l2649
I have often looked at these and wondered would they work just by discharging into the induction for a few seconds? Nothing too complex just a poor mans boost. I would think it would help a bit but would it do harm? Don't know, but it is a very small amount of gas. Got to be worth a few horses, no?