Just thought I would add my two cents on the 87 option. I am running the V3 chip and have had it in since around September. I love it! I switched to the 87 mode when it started to snow and have run about 4 tanks of gas so far. I figured I did not need the extra power in the winter, so I would save money on gas. I really have not seen much of a difference in the preformance yet. It still runs stronger and smoother. I can't say much for the gas mileage.It always is bad in the winter though. I only get about 12-15 MPG. So it really helps to be able to put in the 87 gas. Dave.