While it may have been short lived, the 2018–2023 Kia Stinger was a fantastic sports car. With the 3.3 liter twin-turbocharged V6 Lambda II engine, the Stinger made 368 horsepower and 376 lb-ft of torque. While it is already very formidable straight from the factory, for those looking to really transform the Stinger into a performance machine look no further than a Kia Stinger turbo upgrade. This mod isn’t for the faint of heart, and takes the Stinger to an entirely new dimension. Read on to find out the best Kia Stinger turbo swaps available for the 3.3 Lambda II V6.
Make sure to check out our other Stinger content, including our: Kia Stinger tuning guide, Kia Stinger downpipes upgrade guide, Kia Stinger intercooler upgrade guide, Kia Stinger cold air intake guide, Theta II upgrade guide, Theta II common problems guide, Theta II intake upgrade guide, and our top Kia Stinger performance mods guide. We also have guides for the Hyundai Genesis G70, including our top G70 mods guide, which also uses both the Theta II and Lambda II engines.
Kia Stinger Info and Turbo Upgrade Basics
The base power plant inside the Kia Stinger is a 250 horsepower 2.0 liter turbocharged I4, but this article is geared towards the larger and more powerful 368 horsepower 3.3 liter twin-turbocharged V6 engine. Known as the Lambda II engine, it’s the same engine Hyundai uses in their Genesis G70 sports sedan. Originally in the Stinger, it produced 365 horsepower and 376 lb-ft of torque, but that soon jumped to 368 horsepower, where it remained.
The Lambda II engine uses gasoline direct injection fueling, which is widely seen as the standard for modern sports engines. It helps the Stinger to make its outstanding factory performance numbers, and is very helpful when turning up the boost. This also allows the Stinger to run ethanol without changing out the fuel lines or injectors. Ethanol will help your Kia Stinger turbo upgrades make even more power.
The stock turbos on the Lambda II V6 are two Garrett Honeywell MGT1446SZLK turbochargers. They run variable boost depending on the atmospheric conditions and fuel. Typically, it is around 12-15 PSI at sea level under normal conditions. The Stinger also uses an air-to-air intercooler for cooling the boost. The cylinder heads on the Lambda II engine are designed so that they house the turbochargers themselves. This is instead of having a separate exhaust manifold and cylinder heads.
Typically, the Kia Stinger factory twin-turbo setup is good until around 500 wheel-horsepower with an ethanol flex-fuel mix. Considering a stock Stinger makes 320 wheel-horsepower on pump gas, that’s a pretty considerable upgrade already. Kia Stinger turbo upgrades are really only for those wanting to take their Lambda II to a completely new level.
Kia Stinger Turbo Upgrade Horsepower Gains
The size of your Kia Stinger turbo upgrades will determine how much horsepower you will ultimately make. For upgrading the Stinger turbos you have two basic paths: Either you can upgrade both of the twin-turbos, or you can swap out the twins for a single but bigger turbo. Both of these will produce solid results, but they will also make the Stinger perform very differently.
While it might seem surprising at first, for those looking for the most power, a larger single turbo will generally be the best way to go. While twins will provide quick and sustained boost, a larger turbo will make more peak horsepower in the end. However, the larger the turbo the more noticeable the turbo lag will be, and the less drivable the car will be on the street.
For those looking to keep their Stinger still a daily driver or at the very least street-driven, a twin-turbo setup will probably be the best option. For those looking to make the most horsepower possible for the drag strip or for roll racing, a single “big turbo” will probably be a better fit.
Kia 3.3T Power Limits
Before slapping on a new Stinger turbo and pumping up the boost, it’s important to consider how much horsepower the Stinger engine and drivetrain are capable of handling. From the factory, the GT2 Stinger pumps out 368 horsepower and 376 lb-ft of torque. This equates to roughly 320 wheel-horsepower and 330 wheel-torque on a dyno. As mentioned, the OEM turbo setup is good until around 500 wheel-horsepower/torque on an ethanol flex-fuel mix.
Most people consider the stock drive train to be able to handle about 600 wheel-torque before things start to break. The torque converter is rated much lower than that, and some people experience problems with the OEM turbos while doing launches. In addition, the transmission is about at its limit at 550 wheel-torque.
What does this mean for your Stinger turbo upgrades? Unfortunately, it means things might break after you start making serious power. There are not very many Stingers with upgraded turbos, so those who do are somewhat in uncharted territory. Some people have made more than 800 horsepower and been okay, while others have had problems at just 700 horsepower. Kia certainly did not engineer the drivetrain to withstand anything close to 600 wheel-torque, so it is somewhat of a crapshoot.
Stinger Engine Limits
As for the engine block and internals, those seem to withstand the power relatively well. The only real exception are head bolts, which are not great on the Lambda II V6. The problem seems to be running high levels of boost that exceed 20 PSI. Running too much boost can cause head gasket issues and potentially lifted cylinder heads.
It’s important to keep in mind that larger turbos will have greater CFM, so they will produce more power at the same PSI. So if the engine already struggles with stock turbos running more than 20 PSI of boost, larger turbos will only exacerbate the problem. In theory, you could run the same boost pressure as stock and make more power, thus saving your head gaskets. But with the price of turbo swaps it doesn’t make much practical sense.
As of this writing there are no aftermarket head bolts or head studs for the Lambda II, making this a tricky issue to solve unless you get them custom built. Internally, the rest of the engine seems up to the task. The block is very reliable and the connecting rods are forged. There have not been many reported cases of piston failure, and it seems Hyundai very much overbuilt the Lambda II’s internals (aside from the head bolts).
Once again, you’re in somewhat uncharted territory pushing more than 700 horsepower on the Stinger. The rods and pistons are likely going to fail pretty soon after pushing that much power for more than a few thousand miles, but the dearth of real world reports makes it hard to estimate. If you’re considering a turbo upgrade, be prepared to pay to potentially fix both the drivetrain and engine, which can get costly quickly — in addition to the turbo kit.
Kia Stinger Turbo Upgrade Supporting Mods
If you decide on a Kia Stinger turbo upgrade, there are a few mods you need to consider. The first thing to keep in mind are fueling upgrades. The stock fuel system uses direct injection with no supplemental port injection. The stock fuel system has shown itself capable of 600 wheel-horsepower. For those looking to go even more than that, adding supplement port injection can help, but it does require a separate fuel controller that needs to be integrated into the ECU.
Upgrading the intercooler is also necessary for a turbo swap. The OEM intercooler is only meant for stock boost levels on the stock turbos. It will immediately become overmatched with a swap. You can view our Stinger Intercooler Upgrade Guide for some of the best intercoolers on the market if you’re making your own turbo kit.
Another must have if you swap out your turbos is ECU tuning. The stock ECU will absolutely not be capable of handling new turbos. It will likely struggle to run at all if they are installed without tuning. Tuning the Stinger can be difficult, because the ECU needs to be unlocked or a standalone system needs to be used. If you buy a kit, they usually come with tuning solutions, but if not you will need to find your own tuner. The most widely used solution is the EK1 Lite, which is available from a variety of tuners.
You will also need to upgrade your downpipes and exhaust on the Stinger for a turbo upgrade. The stock downpipes are restrictive with the stock turbos, and they will completely choke off bigger ones. You can view our Stinger Downpipe Upgrade Guide if you plan on sourcing your own.
Turbo Housing and Manifold Swaps
This only applies to those utilizing custom kits with either larger than stock turbos or a larger single turbo. Due to Kia integrating the turbocharger housings with the cylinder heads, unless you are putting on stock sized turbos they will not fit. You also can’t just put on a bigger housing due to its integration in the manifold/heads.
This means that with bigger turbos or a single turbo setup, you will need new turbo housings and custom exhaust manifolds. Most kits include these, so if you want something custom you will need them individually made.
Best Kia Stinger Turbo Upgrades
The best Kia Stinger turbo upgrades are:
- Lap3 Twin-Turbo Kit
- Pure Turbos OEM Turbos Upgrade
- IMR Twin-Turbo Kit
1) Lap3 Twin-Turbo Kit
Now let’s get into the recommendations. First up on our list is the Lap3 Kia Stinger Twin-Turbo Kit. This is probably the most popular Kia Stinger turbo upgrade kits, and it was one of the first successfully to make it to market. The Lap3 kit is a twin-turbo kit that uses dual XCargot XT26 Turbos. Together, they are capable of making 600 wheel-horsepower and 550 wheel-torque.
The kit comes with everything needed, including a larger front-mount intercooler, turbo housings, new manifolds, and new downpipes. You can also select the Lap3 ECU and TCU tuning solutions. The Lap3 is pretty pricey coming in at $12,000 (before tuning), but you can tell it has some excellent craftsmanship and work put into it. There is a reason it is the go to kit for many Stinger turbo upgrades, and it has been shown to perform very well on the streets.
2) Pure Turbos OEM Turbo Upgrade
Next up we have the Pure Turbos OEM Kia Stinger Turbos Upgrade. This is not a turbo swap but instead is a turbo upgrade. Basically, they take OEM turbos and add a custom billet compressor wheel and custom HF turbine wheel. They also upgrade the rest of the turbo’s internals. This allows for stock sized turbos that fit the stock location, but pack a much more powerful punch. They are capable of more than 500 wheel-horsepower, and are a much cheaper option than upgrading to a full kit.
If you do plan on upgrading your stock turbos instead of swapping them, you will still want to make sure you are doing all supporting mods. Upgrading the downpipes and intercooler are still very important, though you likely won’t need to worry about supplemental fueling. The Pure Turbos OEM turbo upgrade is a great option for those looking for a little extra power without breaking the bank with a full kit. You can also send in your stock turbos for a discount.
3) IMR Twin-Turbo Kit
Our final recommendation is the brand new IMR Kia Stinger Twin-Turbo Kit. IMR just released this in May 2023, and it is already shaping up to be one of the best kits on the market. IMR uses a variety of different turbos with their kit from either IMR themselves or Garrett. They claim their turbo kit will be capable of up to 900 wheel-horsepower and includes all supporting mods.
The kit looks fantastic, and routes the air filters in front of the radiator and just behind the bumper. This provides for incredible flow and heat reduction. The green boost tubes are also a nice touch, as is the absolutely massive intercooler. We previously rated their intercooler as one of the best for the Stinger, and the one with their kit appears to be even bigger. The IMR kit is cheaper than the Lap3 at $9,500 and may ultimately make more horsepower. Both are solid options.
Kia Stinger Turbo Upgrade FAQ
The Kia Stinger uses twin Honeywell Garret MGT1446SZLK turbochargers that runs 12-15 PSI of boost.
The best Kia Stinger turbo upgrade kits are the IMR twin-turbo kit and the Lap3 Performance twin-turbo kit. Both of them deliver solid horsepower, with the IMR coming in cheaper.
With upgraded turbos, the Kia Stinger can make more than 900 wheel-horsepower, or over 1,000 crank-horsepower with the IMR twin-turbo kit.