Superchips Flashcal Speedometer Calibrator and Diagnostic Device 01-16 GM 6.6L Duramax YUK-YG C9.25R-411R-14 but you've forgotten one of

but you've forgotten one of the most critical components causing your bottleneck

or changed the rear gear ratio

big top-end power

you'll benefit from added horsepower

3L Turbo Thruster for the 1999

Superchips Flashcal Speedometer Calibrator and Diagnostic Device 01-16 GM 6.6L Duramax YUK-YG C9.25R-411R-14 but you've forgotten one ofUpgrading your Chevy or GMC to larger tires is one of the most popular upgrades. That said, recalibrating your speedometer typically would require a trip to the dealer. Especially if you are prone to swapping betwen tire sizes for winter or other purposes, this can be a cumbersome effort running back and forth. Further, when a check engine light pops up, wouldn't it be nice to find and clear the code yourself? The Superchisp Flashcal is a product