Why Should I Upgrade My Cummins Turbo?

For those with a Cummins truck, be it a 5.9 or 6.7, we all know the turbo is one of the go to upgrades for any diesel. It provides lower EGTs, quicker throttle response, and adds even more reliability to already extremely durable engines. If you seek even greater power, or are simply looking for a more responsive vehicle, we all know having a larger turbo is always a good go to upgrade!

In all seriousness, upgrading the turbo in your vehicle is going to offer you the most bang for your buck in terms of performance. If you want further fuel efficiency, upgraded performance, and greater EGT efficiency, adding a larger turbo seems to be the best option.

Factory Turbos Have Their Limits

Stock turbochargers on 5.9L and 6.7L Cummins engines are built for emissions compliance, fuel economy, and low-end torque—not power. If you add tuning, lift pumps, or even injectors, the modifications will change your vehicle significantly and the stock turbo will simply become a bottleneck with no additional benefit.

If your turbo has any of the following signs, it may well be time to replace it:

• Sluggish spool-up
• High throttle drag
• Throttle lag
• Turbo surging under load
• Inability to accelerate without smoking

All of the above could be solved by switching to a performance turbo, as they are designed to provide better cfm (cubic feet per minute) at lower boost pressures.

Support Increased Horsepower

Performance turbos are created with the intention of moving air efficiently. Sometimes, we might go for 500 hp but most often it ranges above 1,000 hp.

For instance:

A drop-in S300 or S400-based turbo can easily support 600–800 hp.

Compound turbo setups or larger singles can push well past 1,000 hp.

Upgraded VGT turbos such as those for the 6.7L Cummins offer greater drivability and higher boost and airflow.

Without these upgraded turbos, further modifications will not be able to meet their full potential.

Decrease EGTs and Boost Efficiency

If a stock turbo is worked harder than its meant to, it will severely increase exhaust gas temperature. This will melt the engine shaft and system valves leading the turbo to failing.

Upgrading the turbo will increase the air intake allowing the engine to burn fuel completely which will accomplish:

Lower EGTs under load
Better combustion efficiency.
Cooler operating temperature when towing or hauling.

This is a must for tuned or work trucks driven in hot weather or tough climbing conditions.

Improved Throttle Response And Spool-Up

Performance turbos can now be offered with faster spooling designs like ball bearing, optimized turbine wheels, and tighter AR housings. This provides:

Reduced lag.

Faster response to boost.

Better low-end torque.

Smoother acceleration.

There is no need to give up drivability on the Cummins turbo upgrades for added performance. Many upgrades retain daily-driver usability.

Increased Reliability and Durability

Aftermarket turbos are often built with higher quality parts and include chrome plated bearings, upgraded seals, and precision balanced internals. These parts give aftermarket turbos the ability to endure stronger abuse, higher boost, and greater sustained added heat.

With proper install and tuning, an upgraded turbo will often outlast the factory unit, especially with modifications.

Enable Future Modifications With Turbo Upgrades

Use the turbo upgrades as a starting point for further changes down the line like tuning, fuel injectors, and even compound turbos.

The stock cam can get tossed aside and the rest of the setup maxed out for credible power outputs, leading a lot of Cummins and other turbo enthusiasts to depend on discharge, letting with the stock setup then based on.

Final Thoughts

The short answer: it depends on how you drive your truck. If you regularly tow heavy loads, daily drive with a tune, or undoubtably plan to build the truck long term, then upgrading the turbo is advisable.

It will not only increase power and reduce temperatures, but it will also give your truck the ability to grow safely and reliably.

Are you ready to upgrade? Whether you need a drop-in replacement, a single VGT upgrade, or a complete compound setup, remember to tailor your turbo to your fuel system, objectives, and driving style. If you need assistance selecting the right configuration, the Tameless Performance team is available to assist.