Kia Stinger Performance Upgrade Guide

The twin-turbo 3.3L version of the Kia Stinger has a very strong engine. Just a few bolt-on upgrades like tuning, an intake, downpipes, and intercooler can get these engines very close to 500whp, and the factory block and internals can handle nearly 800whp.

In this guide we’re going to discuss five Kia Stinger performance upgrades that can add tons of power for less than $2,000. These mods are also applicable to the smaller 2.0T engine, you just won’t experience the same level of power gains of course.

Kia Stinger Performance Upgrades

• Tune
• Intake
• Downpipe
• Intercooler
• Full E85 / Chargepipe Injection

If you would rather consume this content via a video, check out our Best Kia Stinger Mods video below:

Pre-Tuning: Spark Plugs

The stock spark plugs on the Kia Stinger are prone to spark plug blowout and misfires once extra boost is added. Therefore upgrading spark plugs to a “colder” plug is a must if you plan on running a tune on your stinger. Your two options are 1-step and 2-step colder spark plugs. 1-step colder plugs are good for any Stinger that is full bolt-on and under the 500whp mark. If you are planning on upgrading turbos and running past 500whp then we recommend 2-step colder plugs.

1-Step Colder Kia Stinger Spark Plugs
2-Step Colder Kia Stinger Spark Plugs

1) ECM Tuning

The hands down best bang-for-the-buck mod on a Stinger is a flash or piggyback tune. The internals on the 3.3L are considered good up until about 800whp and the stock turbos are safe for around 475-500whp. With a stock 3.3 Stinger dyno’ing around the 350whp mark, Kia left a lot of power potential on the table, likely for the sake of reliability.

Tunes primarily increase power by increasing the amount of boost from the turbo. Since there is a lot of room between the stock power levels and the safe limits of the engine and turbo, the boost can be turned up a sizeable amount to create some significant power gains. Additionally, a tune is great for additional modifications as it adjusts various engine variables like timing and fueling to coincide with the cars existing mods, therefore maximizing power gains from the other mods and creating a healthier engine overall.

Price per horsepower, you aren’t going to beat a tune. If you are only going to make one mod to your Stinger, this is the one we recommend. The ability to easily switch between different maps and turn the tunes on and off on the fly makes them user friendly and a great mod for beginners.

Benefits

• Up to 80whp and 100wtq gains
• Plug-and-play and user friendly
• Pre-packaged with various maps for different power levels
• Maximizes other mods power gains
• Overall healthier engine

2) Cold Air Intake Upgrades

More power requires more combustion and combustion requires air. Once you add a tuner and increase boost it is important to bring more air into the engine to reduce stress on the turbo. At stock power levels the factory intake is fine, but once boost is added it is awful and becomes highly restrictive. Therefore replacing the factory intake with a cold air intake is a must for tuned Stingers.

Now the term “cold air intake” isn’t necessarily accurate here. The intake systems for the 3.3TT engine sit within the factory air box location rather than being routed to a lower portion of the engine bay to pick up colder air. Instead they remove the factory boxes and use a larger filter to draw more air in. Air intake temps don’t necessarily matter on turbocharged engines since the air is heated anyways as it passes through the turbo, and is then cooled once it enters the intercooler.

Overall, an intake is probably the second best mod for a Stinger and a must-have for anyone running the JB4 or other tuner. Our only recommendation is to stick with an open intake system like Boosted Performance’s intake instead of a system like Stillen which is partially enclosed and therefore more restrictive to airflow.

Benefits

• 15-25whp and similar torque gains
• Improved airflow
• Reduced stress on the turbo
• Cool intake sounds

Boosted Performance Intake

Not only does Boosted Performance offer the best intake on the market, it is also one of the most affordable at $299. Their dual intake system uses significantly larger, high quality S&B filters that has one of the biggest, if not the biggest, airflow increases on the market. It is a direct bolt-on replacement to the stock intake system and works with aftermarket inlets too.

Combining the Boosted Performance intake with a tuner will add upwards of ~25whp. These are amongst the best gains on the market. However, as a side note, don’t expect to see power levels like this from their intake, or any other intake alone. An upgraded intake on an otherwise stock Stinger will probably provide 8-10whp gains. Getting above that will require combining the intake with a tune and increased boost.

Price: $299

Buy Here: 3.3L Stinger Boosted Performance Intake

Make sure to check out our Kia Stinger cold air intake guide for even more Stinger intake info and recommendations.

3) Upgraded Downpipes

The downpipes bolt-up directly to the turbocharger and is the first component of the exhaust system in the Kia Stinger. Since the downpipes sit so close to the turbo it creates a ton of backpressure on the turbo and turbine wheels.

Also, when you have an intake and a tune you are creating more exhaust gases. This amplifies the backpressure on the turbo and hurts performance, increases EGTs, and reduces turbo reliability and efficiency.

Therefore, we recommend upgrading the downpipes. On a stock Stinger, the gains will be minimal. But definitely not when tuned. And not to mention, they reduce turbo stress which improves turbo reliability.

Benefits

• +15-50 horsepower and torque
• Reduced exhaust backpressure
• Improved turbo efficiency and reliability
• Slightly louder exhaust note

Make sure to check out our Kia Stinger Downpipe Upgrade Guide for the best downpipe recommendations.

4) Performance Intercooler Upgrades

Another crux of the factory Stinger components is the stock intercooler, or FMIC. Like all other components, it’s fine when the car is stock but once it is tuned and modded it becomes restrictive. The factory intercooler is tiny and therefore can get overwhelmed easily when you are tuned and driving aggressively, doing back to back pulls, whether on the street or track. It causes the turbos to experience heat soak, which reduces performance.

Upgrading the intercooler involves getting an FMIC with a larger core and end tanks and therefore has more cooling capacity. Stinger intercooler upgrades don’t necessarily provide huge power gains but it provides more consistent performance and prevents you from losing a lot of power. When experiencing significant heat soak, you can lose 30-40whp with the stock intercooler. An upgraded intercooler will provide you about 10whp and prevent heat soak, therefore preventing you from losing 30-40whp.

Not only is it great for performance, it’s also great for reliability. Heat is the killer of all engines. In our minds, this is a must have if you are tuned and running an intake.

Upgraded Intercooler Benefits

• ~10whp gains
• Prevents heat soak
• More consistent performance during aggressive driving
• Lower EGTs and improved engine reliability
• Improved boost capacity

5) E85 Fueling & Chargepipe Injection

Before we get further into this, I’m going to note that CPI fueling and full E85 aren’t necessary unless you are planning on upgrading your turbos. The stock turbos are good for 475-500whp and you can brush right up against those numbers with a tune, intake, intercooler, and downpipes. Therefore, fueling mods are really needed unless you are going to surpass these levels. Also, pushing about $800 this is the most expensive mod on our list.

The first option is running full E85 fueling. However, the stock HPFP is a limiting factor here as is the LPFP. To run 100% E85 you will need to run an upgraded LPFP and chargepipe injection. With a performance HPFP running $1,500+, chargepipe injection is the preferred route. And keep in mind you will need a flex fuel kit to monitor ethanol fuel mixes. E85 mixes can provide 20-30whp gains and full E85 can provide 50whp+ depending on mods and tuning.

The second fueling mod is chargepipe injection. Note this is still good for people running good ole pump gas, but can also be used for ethanol mixes, but running 100% E85 will still require other upgrades. The alternative to upgrading the HPFP is to add a 7th injector to the chargepipe which is capable of providing about 75-100whp of capacity over the stock fueling limits which are right in line with the turbo limits.

Summary

With the stock turbos capable of handling 475-500whp on the 3.3L Stinger and internals that are good for near 800whp, there is a ton of room for performance upgrades. Simple bolt-on mods like a tune, intake, downpipes, and intercooler can push the Stinger in the range of 475whp for just a few thousand dollars. For those looking to eclipse the 500whp mark, you’ll need to add upgraded turbos and additional fueling via chargepipe injection or HPFP/LPFP upgrades.