Best of Diesel is reader-supported. When you buy through links on our site, we may earn an affiliate commission.
Whether turbos are used in computers or cars, the word is synonymous with speed, power, and efficiency. But here we are going to focus on cars and, more specifically, the 12-valve Cummins diesel engine. This engine was specifically designed for heavy-duty work and is famous for being a fully mechanical engine.
Turbos were designed in the 1970s as a solution for the rising environmental problems caused by in-efficient engines that were not properly consuming fuel. A turbo or turbocharger forces compressed air into the combustion chamber, which accelerates the combustion process.
As good as they are, they do need to be changed every 100,000 to 150,000 miles. So before we get into the best Turbo for 12V Cummins, let's first see if you need a change and how to properly select the turbo for your engine.
At a Glance: Our Top Picks for Turbo For 12v Cummins
- OUR TOP PICK: Blackhorse-Racing Diesel Turbocharger 3592766
- BEST BUDGET OPTION: Stigan 847-1041
- BEST 12V CUMMINS TWIN TURBO: Diesel Power Source S480
Comparison of the Best Turbos For 12V Cummins
| IMAGE | PRODUCT | |
|---|---|---|
Our Top Pick  |
| View Latest Price → |
Best Budget Option  |
| View Latest Price → |
 |
| View Latest Price → |
 |
| View Latest Price → |
When is it Time to Replace the Turbo on a 12V Cummins?
You’ll probably be able to tell when there is time for a change because your car will tell you by lower speed, noise, smoke, and the check engine light. The turbo’s main function is to improve your speed, so if there is something wrong with it, you’ll immediately notice a lack of acceleration and power.
Blackhorse-Racing Diesel Turbocharger 3592766
Another thing to look for is the noise, which is something you should definitely get checked from the mechanic to determine if it is turbo-related. The turbo is a part of the engine that is bound to degrade over the years, but you can improve its life by following some simple rules:
Do not use poor quality oil as it leads to contamination in the engine.
Do proper maintenance of the oil and air filters.
Check for any leaks and make sure all the parts of the engine are in good condition.
When the time eventually does come for a new turbo, you should look for only the best and the ones that will add to your performance. There are many different kinds of turbos that you can choose from, so before selecting let’s, look at these types.
What Kind of Turbo Should I Get for My 12V Cummins?
There are essentially six different kinds of turbos. We will list them all down and discuss them briefly here.
Single
This is the most popular as it is the cheapest and works best with smaller engines. It has a very versatile design, as by changing the sizes of its components, you can achieve different outputs.
The smaller turbos from among them are used when you need better low-end power or better torque (how fast the engine spins). If you want more horsepower, the bigger-sized turbo will work better as they give more high-end power. Despite being affordable, this type has its issues because it can give substantial results within a limited rpm range.
Diesel Power Source S480
Twin
Twin-turbo is basically two single turbos working together. With these, you have two options, i.e., both turbos of the same size or one bigger than the other. Whichever one you choose overcomes the problem of choosing between high and low rpm performance.
When using a twin-turbo with two similar-sized turbos, you use one when at low rpm and both together at high rpm. The different sized turbo combination uses bypassing. The smaller one is used at low rpm, which is then bypassed by the larger turbo when at high rpm.
This option is, however, too complex and expensive for most people.
Twin-Scroll
This is probably one of the most efficient configurations which come with a price, but it just might be worth it. It doesn’t use two separate turbos; rather, it uses two scrolls. The turbo takes exhaust gases from the engine, and instead of expelling them, it uses them to push more air in the combustion chamber.
The problem arises when gases from different cylinders cycles overlap (one cylinder could have an open exhaust valve while the other could have an open intake valve). As a result, the compressed air coming in becomes contaminated, and the pressure by which it forwarded is reduced.
Twin-scrolls use two scrolls that work with separate sets of cylinders that provide the gas. This way, there is no overlap, and efficiency is increased substantially.
Variable Geometry
The job of every turbo is the same. How it goes about it differs from design to design. Variable geometry design is used most commonly in diesel engines. This ingenious design uses variable or changing geometry of its vanes (as the name suggests).
When in need of more torque or in low rpm, the area-to-radius ratio of the ring of vanes is decreased and vice versa for high rpm. This increases the effective rpm range without having to add an extra turbo.
Variable Twin Scroll
To get the best of both the twin-scroll engine with variable geometry, you can choose this option that combines the variable geometry of vanes with twin scrolls. Since variable geometry turbos are mostly only practical in diesel engines, there was a need for petrol engines that this type fulfills.
It works by placing a valve between the two scrolls, which is closed at lower RPMs to divert all the exhaust gases in one scroll and increase pressure. It is then opened in increments and by small amounts for higher RPMs.
Electric
Normal turbos have some lag in them, which occurs when they are spooling up. To get rid of this, some manufacturers make use of electric compressors. When the turbo is working at its full potential, the compressor gives the car the boost it needs, virtually removing any lag.
This system is very expensive and complex as it requires a motor. This also causes weight and size issues. But you have to decide which is more important for you.
How to Choose a Turbo For a 12V Cummins
There are various aspects that go into choosing a turbo, which includes the configuration discussed above. That is the first step, but there are other specifications (durability and strength are a given) you should keep an eye out for.
Boost
Wanting more speed and power is great, but if your engine cannot handle it, you are going to end up doing more damage than good. This is why you should check the effective boost capability of the turbo before putting it in.
For a 12v Cummin engine, it is recommended to stay in the 35-40 psi range.
Installation
Turbo installation is not an easy process. When you are deciding your budget, make sure to consider how the installation cost of this particular turbo. It can vary widely, depending on the complexity and model.
If you are planning on doing it yourself, you should probably opt for the product that has an easy-to-understand manual and good online help. This article will also cover the installation process later on.
Budget
Depending on the complexity of your system and if you are planning on buying turbo accessories, your budget can overshoot. The installation is also not inexpensive, but when setting everything up, you need to prioritize first getting the most practical rather than the fanciest choice.
Review of the Best Turbos For 12V Cummins
Now that you have the basic picture of what you need to look for, let’s take a look at the best turbos for 12v Cummins.
Best Overall:
Blackhorse-Racing Diesel Turbocharger 3592766
PROS
CONS
What Recent Buyers Report
This is a very affordable replacement model for when the factory turbo needs changing. On a Dodge Ram Truck, it makes a huge difference, and you can feel the power kick in, especially if you have been driving on a very old turbo.
Why it Stands Out to Us
This turbo gives you up to 270 horsepower, which works fine with a 12v Cummins. It will maintain the perfect fuel-to-air ratio in the combustion chamber to keep giving steady power to the car.
It is made with highly durable material so that you can get the most out of your investment.
Bottom Line
With this model, you don’t need to make any changes; it will fit right in the engine. You will experience a boost in horsepower and torque output. But don’t overexert it or expect it to go beyond 270 hp. This will be enough for your Cummins.
Best for the Money:
Stigan 847-1041
PROS
CONS
What Recent Buyers Report
Many buyers report that this model is extremely cheap, considering it gives you OEM specifications. It works great on a truck and can handle some towing as well. Given its price, this is probably the best you will get.
Why it Stands Out to Us
We like this model as it is designed with OEM specifications and comes within legal emission rates in all 50 states. This is a twin-scroll type turbo that gives you performance without the need for extra turbos or electronics.
This model has been tested with extreme conditions to give consistent power and efficiency. The manufacturer uses ISO certified factories so you can expect to get OEM matching standards.
Bottom Line
Overall, this model gives you power that you would otherwise get from a complicated and expensive turbo. It is designed with the highest quality materials in mind so that it is durable and reliable, making it a great investment.
Best 12V Cummins Twin Turbo:
Diesel Power Source S480
PROS
CONS
What Recent Buyers Report
According to users, this turbo gives you room for improving horsepower significantly. You can do 45, 60, or 70 psi as it is adjustable. You can definitely feel a significant improvement in performance here. Depending on your truck, it goes to 800 hp as well.
Why it Stands Out to Us
It stands out to use because it is a twin type turbo with an adjustable boost. It can go as high as 70 psi but can be adjusted to lower levels, depending on the truck. It will also reduce the EGT (Exhaust Gas Temperature) by 300 degrees, making for a cooler engine.
It works well in both spooling (giving high torque) and improving airflow (giving high horsepower) because of its twin design.
Bottom Line
Twin turbos, though a little complicated in design, make for a great option when you are looking to increase the effective rpm range of your turbo. This one does exactly that. It is designed to be easy to install without needing to cut or change anything.
Editor's Pick:
CXRacing HX35W 3539373
PROS
CONS
What Recent Buyers Report
Recent buyers had a great time using this turbocharger because of its powerful performance. They liked how it adjusts to the needs of their engine well. Buyers also came up with positive feedback regarding the price-to-quality ratio. They found it both affordable and reliable in terms of working.
Why it Stands Out to Us
It catches our eye with the standard T3 turbine housing flange. It has the perfect size for most Cummins engines, whether new or old. It comes well-tested and has computer balancing of all the vaults and exhaust vents. This makes it quite popular among users who want a quick engine charging.
Moreover, its compressed air outlet has a width of 2.25 inches, making it more efficient. This turbocharger has a safe exhaust valve, which keeps the engine working in a regulated environment.
Furthermore, it has an oil-based cooling mechanism that prevents any friction, making its working even better.
Bottom Line
All in all, it is an amazing engine charger which increases the life of your Cummins engine. The 5.9L diesel engine ensures maximum speed and fuel efficiency on the roads. So, you should consider it seriously before investing in a turbocharger.
5. Stigan 847-1432
PROS
CONS
What Recent Buyers Report
Users report that this turbo gives you great quality for the price. You can expect a perfect OEM level performance from this model. It’s cheap, works great, and is comparatively easy to install.
Why it Stands Out to Us
This is an electric turbo equipped with a powerful compressor. The electronic actuator has been calibrated for you to make installation a little easier. Since it follows the exact OEM specifications, you don’t need to make any changes to make it fit in.
It is designed to give you fast and reliable performance that matches if not exceeds, the original manufacturer part. The electronic compressor also reduces the noise significantly.
Bottom Line
If you love electronic turbos and want to get rid of any lag in your startup, then this Stigan model is the choice for you. If you are not looking for a cheap replacement part and want something that will give you the same performance as the original, this will not disappoint.
Pros and Cons of Upgrading Your 12V Cummins Turbo
Having discussed turbos in detail, you probably know why you need a new one. But let’s list down the main points to remember when deciding between if you should get a new turbo or not.
Pros
The following are some benefits of upgrading your turbo
Increase Speed
Now, this is a given. If you choose the right turbo, it will give you significant improvement over the older one. Old turbos lose their efficiency and might even have contaminations build-up inside, blocking good air.
So a good servicing and a new model will improve your driving experience.
No More Noise
A side effect of adding a turbo to your engine is that it reduces noise. One way of telling if your turbo needs changing is excessive noise from the engine, as we discussed before. So if you want a quieter drive, then get a new turbo.
Reduce Exhaust Emissions
Because these devices take exhaust gases and push them back in to give the combustion chamber more air, the release of harmful gases in the air becomes significantly lower. It was designed in the 1970s during the oil crisis when the fear of air pollution was rising, and this was seen as (and still is) a good solution.
Cons
However, even these upgrades have some limitations.
Expensive
Despite all of their benefits, these turbos, especially the good ones, are expensive. There are also a lot of accessories that people use with them to improve the boost it gives, so it adds to cost. And let’s not forget the installation.
Complex
They are also complex designs and cannot be put in by amateurs. Some of them might even require you to cut some things and make changes in the engine, which is not always recommended.
How to Install a Turbo on a 12V Cummins
We have been talking about turbo installation like it’s something to be feared, and it can be for someone who is new to this. To help you get a basic understanding of the procedure, let’s take a look at the steps you have to follow.
- Torque the bolts on the CAB manifold to 35 pounds
- Bolt in the bracket to the 4th and 5th cylinder at the bottom
- Drill in a dash ten fitting for the oil drain
- Screw-in the metric fitting (dash 4 AN) on the oil inlet
- Put the turbo on the manifold
To get a better understanding of the procedure, watch the video given below.
Conclusion
Now that you know what you are looking for, you can easily choose the right turbo for your engine. Just remember the limits of your car and engine and opt for a professional’s help to install the turbo. All the products on our list have been selected because they give OEM level if not better performance. Choose anyone, and you will be good to go.
People Also Ask
If you are still confused as to which turbo to buy or have any questions regarding 12V Cummins, read these frequently asked questions for guidance.
How Do I Get More Power Out of My 12V Cummins?
Adding a quality turbo is one of the ways you can increase the power you are getting from your 12V Cummins.
How Much Horsepower Does a 12-Valve Cummins Have?
The 12v Cummins has 300 to 350 horsepower. It might differ depending on the model and year of make.
How Long Will a 12-Valve Cummins Last?
Cummin engines, if properly maintained, can last for as long as 600,000 miles or more.
