As GM 3.6 specialists, we offer the best tuning and unique products for your 3.6 motor. Our suggested modpath for the 2014-18 Impala and its similar platforms is as follows:







We are pleased to be a premier tuner for the 2012+ GM 3.6 Direct Injection V6, codename "LFX", found in your 2014 and newer Impala, 2013+ Cadillac XTS and 2012+ Buick LaCrosse.

We've long been GM V6 tuning specialists, tuning sedans like these that people have bought for practical purposes but want that extra performance. If you want your 300 V6 to feel like 300 horsepower and beyond, that's what Overkill tuning can do for you. Overkill LFX tuning is a performance recalibration of the engine and transmission computers. The benefits of an Overkill tune are straight forward: More power, more instantaneous, improved transmission performance, and proper support for your additional modifications. Whether you're an enthusiast or consider yourself a regular car owner, these are changes that you'll appreciate and enjoy every time you drive your Impala, XTS or LaCrosse.

Features/Benefits:
  • Horsepower and torque gains of 15-30 on 91 octane and 10-15 on 87 octane anticipated
  • Stronger mid-range power, less peaky feeling to the power delivery
  • Improved throttle response, more natural and consistent throttle feel
  • Increased fuel mileage capability, will depend on your driving style
  • Overkilled transmission revises the part throttle shift pattern will downshift with less throttle input, upshift at better engine rpms, reduce torque converter bogging around town, and improve how the vehicle feels in daily driving by feeling lighter and easier to drive
  • Support for your other aftermarket modifications including our intake system, aftermarket exhaust systems, our 80mm throttle body, JacFab intake spacer and more.
  • Speed Limiter Removal, Engine park rev limiter raised
  • No charge revisions for your future modifications, including no charge for our throttle body upgrades


What you'll get with your purchase:
  • An Autocal handheld tuning device, with software on a USB drive
  • Overkill 91/93 octane tune
  • Overkill 87 octane tune
  • Overkill E85 Flex Fuel performance tuning in each tune (if you have an E85 Flex Fuel ready vehicle)
  • Tuning support for datalogging and custom revisions
  • Tuning support for new mods as you add them, for as long as you own the vehicle


Why get an Overkill tune versus the competition?
  • Specialized in the LFX motor. From revised cam phasing, fully reconstructing spark timing tables and fully revised throttle calibration, an Overkill tune is more comprehensive than what you'll get at your local dyno shop. Our tuning includes comprehensive peformance calibrations on both regular and premium gasoline, and on E85 Ethanol; our competitors commonly don't offer 87 octane or E85 performance tuning.
  • Datalogging. You'll get your Overkill tunes but it doesn't stop there. You can scan with our handheld while driving and send that data for review and tune updates, to get a tune that's more customized for your vehicle. Our main competitor offers this service for significant extra fees
  • Support for your mods. Not only are we the only company with an E85 Flex Fuel conversion kit or a larger 80mm throttle body kit, but we also have the right tuning to ensure you get the most from them! Our main competitor offers a preset tune meant for 100% factory unmodified vehicles only
  • Retunes. With our handheld, retuning for your future modifications is complimentary and easy to provide




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Autocal Handheld: The best way for us to provide tuning for your 2014+ Impala is through our Autocal handheld system. The Autocal handheld allows you to take the handheld to the vehicle, read the factory file, upload our Overkill tunes and provide scan data using just the handheld unit inside the vehicle. Return to stock calibration whenever you want, apply updates and retunes easily through email with us and Overkill retuning is available at no charge for as long as you own your vehicle. You'll need a computer that can run a windows based program and has a USB port to transfer files to and from the handheld.





The only intake on the market for the 2014+ Impala. This replaces your factory air filter housing, tubing and MAF sensor with new tubing and a large cone air filter. While an open cone, it greatly improves air volume into the engine and adds a great sound while accelerating. The intake shown has a black filter, but the intakes we ship now include an Amsoil air filter with prefilter that is blue in colour; you'll get it, with a silicone coupler, a top quality aluminum MAF housing and associated hardware.

Paired with it is a our 80mm throttle body for the 2012+ 3.6, another Overkill exclusive. This throttle body replaces the small 72mm factory throttle body to improve throttle response and top end horsepower up to 9 wheel horsepower. The intake manifold inlet is already 80mm, as shown in picture, so this throttle body maximizes the flow potential of the factory intake manifold. Since the air intake pairs perfectly with the 80mm, we sell and recommend them as a paired combo, but you can also purchase the 80mm separately.

Special Note: This intake REQUIRES Overkill tuning to account for the new MAF sensor size, and the 80mm throttle body also requires tuning on 2014+ Impalas for proper operation or you may get a P0068 code on the factory tuning. The 80mm will not fit the factory intake tubing, you'll need a bigger tube if not running our intake system. It's recommended you only purchase these items if you have Overkill tuning, are buying Overkill tuning at the same time, or have your own tuning method already in place. This will not work on the factory tuning.

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