I know the SCT and Diablo tuner web sites state that "unless otherwise stated the tunes require premium gas...". They seem to imply if not outright state that installing a tune and not using premium gas you will not get any horsepower increase. This may be true but if adding mods like a cold air kit requires a computer reflash, giving it a tune, this would seem to mean that if you mod your car you will no longer be able to use 87 octane gas. I understand that putting in high compression pistons or a hot can would necessitate the use of premium gas but simple bold on mods? I was always under the impression that it was just that the cam and the compression ratio that mainly determined whether or not you would have to use premium gas. It would be nice to do some mods and not have to spend more on gas even if it means not getting quite as much in the way of hp gains. At least there would be some performance improvement. Maybe I'm just dreaming.