I thought I would post this info for those of you curious about the difference between the Hypertech Max Energy and E-Con programmers. I never could find any resources stating the differences between the two, so I sent an e-mail to Hypertech's technical support. Here is what he said: "The E-Con unit is a slim down version of the Max Energy. The E-Con has our Power Tuning for 87 octane fuel and will read and clear dtc's (diagnostic trouble codes). The Max Energy has the same 87 octane tuning plus our tuning for 91 octane. Depending on application the Max will offer the following: Shift point adjustments Shift firmness Speedometer calibration for tire/gear changes Rev (rpm) adjustment Speed limiter adjustment Cooling fan on/off settings Both our 87 and 91 octane settings are primarily designed to increase power. Since we optimize the air/fuel mixture and timing curve the mileage is usually improved also. From many customer testimonials many see 1-3 mpg better. You get much more for your money with the Max Energy." He later clarified that the options he lists (shift point adjustments, shift firmness, etc.) are only available with the Max Energy. So, for those of you trying to decide between the two, hopefully this will help!