

If you have a 2012 to 2013 model year Cadillac CTS sedan, or 2014 CTS coupe, with the 3.6 Direct Injection V6, verified by the 8th digit of your VIN being a "3", you're on the right page for your vehicle!
As GM 3.6 specialists, we offer the best tuning and unique products for your 3.6 motor. Our suggested modpath is as follows:
- Overkill Tuning - Provides the biggest bang for your buck, improved throttle response, transmission shifting, harder acceleration, and will support new modifications as you add them so it's not a one and done deal
- E85/Flex Fuel - Get our E85 Flex Fuel retrofit kit if you have access to E85 in your area. Running the Overkill E85 tune over Overkill 93 octane tune is worth a dyno tested 16 wheel horsepower improvement. It's an easy installation and you can run gasoline or ethanol or any mixture of once installed and tuned.
- Intake system - Air intake systems are available from several companies, though I would save your money, drill your lower air housing to allow more air to enter, and replace the panel filter with a K&N filter if you desire. Changing to a larger 3.5" diameter intake would be worthwhile, but will require tuning
- Overkill 80mm Throttle Body and JacFab Ported Intake Manifold - These go hand in hand together. The Overkill 80mm replaces the little 72mm factory throttle body. The ported manifold opens up the manifold inlet to 80mm and fills in a turbulent entrance cavity to improve flow. Together they add up to 20 wheel horsepower. Now is when you should look to upgrade the size of your intake tubing as well, the factory tube won't fit the 80mm opening.
- High Stall Torque Converter - This mod is ambiguous on where it fits on the modpath. If you want to drop nearly a full second from your 0-60mph time and launch hard from a standstill, a high stall torque converter is one of the best mods for the 3.6, which is a high rpm motor. It's a significant install but worthwhile. Overkill tuning is recommended before doing the torque converter.
- More minor mods - Exhaust work is small gains on the 3.6, you can install the mufflers you like and gain more sound than horsepower, and there's also the JacFab intake manifold spacer which improves midrange torque and is worth considering if you mainly accelerate in the 3000-4000rpm range.
- Supercharger! - For the ultimate mod, look at our Overkill Supercharger system, achieve 100-200 horsepower gains all depending on your goals and budget with bolt on modifications
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Overkill is proud to be a specialist of the GM Direct Injection V6 family and with a special focus on the 3.6 LFX V6. With Overkill tuning, you'll notice right away much improved throttle responsiveness and acceleration and improved transmission performance which will feel lighter and easier to drive. We also support many of our exclusive performance products including E85 flex fuel tuning. What you'll notice:
What you'll get with your purchase:
Why get an Overkill tune versus the competition?
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![]() Autocal Handheld: The best way for us to provide 2012+ CTS 3.6 tuning for you 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, with no laptop required. 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 CTS. |
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This combo pairs Overkill Tuning through our Autocal handheld with our E85 Flex Fuel kit. You'll get Overkill tuning for 87 and 91/93 octane gasoline, plus tuning for E85 Ethanol fuel which out performs its gasoline counterparts. The flex fuel kit retrofits a GM flex fuel sensor into the fuel system, and relays a precise ethanol content of the fuel in the system to the computer. In combination with Overkill tuning, the computer will adjust air/fuel targets for any ethanol blend. You can switch between gasoline and E85 ethanol as desired without requiring any changes to the vehicle once this kit and Overkill tuning is installed. Simple installation will take you 30 minutes. This is by far the best bang for your performance buck on a 3.6 LFX V6! ![]() |
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The only larger throttle body for the 2012+ LFX 3.6 is available here at Overkill. The factory throttle body is 72mm, as are ported units on the market. Our 80mm throttle body solution dwarfs the stock unit and will allow the your engine to breathe, improving horsepower, improving throttle response (particularly with Overkill tuning) and changes the intake note of the V6 to a deeper growl at heavy throttle. This kit bolts to the stock intake manifold with no tuning required, yet works best when used with a ported intake manifold modified to a matching 80mm inlet. Kit uses a brand new throttle body with an aluminum adapter plate and stainless steel bolts. Newest kits now come with an o-ring seal! There is no core charges, we don't need you to send in your factory throttle body. Tip: This throttle body has a 3.5" clamping area, compared to the factory throttle body of 3". Ensure you have a solution available before installing the throttle body! Look below for what we offer for your current intake. For K&N owners, use this 3.5" to 3" straight reducing coupler http://www.siliconeintakes.com/intake-pipe-reducer/tube-reducer-p-74.html ![]() |
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