Duramax LB7 Cold Air Intake Ultimate Guide
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The Duramax LB7 V8 engine is one of the most popular diesel platforms today. The LB7 lasted from 2001–2004, and was the first Duramax engine GMC released. From the factory, the Duramax LB7 produced 235–300 horsepower and a whopping 500–520 lb-ft of torque. While these were substantial power figures in the early-2000s when GM created the engine, modern diesel V8s can easily double that output. That makes modding the LB7 a top priority for many owners. So, today we’re discussing the top Duramax LB7 cold air intake upgrades available. Read on to find out which intakes make the most horsepower at the best price.
What is a Duramax LB7 Cold Air Intake?
For many Duramax owners, a cold air intake is one of the first modifications they do. We have it listed on our top LB7 performance upgrades article, and it is a very popular choice. Air intakes are the first step in a car’s intake system, and they draw in fresh air from the atmosphere. On a turbo-diesel, air intake systems consist of an air filter, and tubing that connects the air filter to the turbocharger. They also may or may not have an airbox, which most factory intakes have.
The purpose of a performance intake on the Duramax LB7 is to increase the velocity and amount of air the engine can take in compared with OEM. The more air an engine can receive, and the faster it can take it in, means the more horsepower and torque it can ultimately make. Versus OEM, performance intakes use larger filters and wider and less restrictive tubing. Generally, this can result in gains of 10-15 horsepower and 10-15 lb-ft of torque.
Short Ram vs Cold Air Intakes
There are two main types of performance intakes, an LB7 cold air intake or LB7 short ram air intake. The difference between the two is generally the length of the piping and location of the air filter. On LB7 ram air intakes, the distance between the filter and the turbocharger inlet is as small as possible. This allows for the least restriction and quickest path for air to travel into the engine.
On an LB7 cold air intake, the tubing reroutes the engine filter towards the fenders or wheel-wells. This gets it as far away from the engine as possible. That allows for colder air that is more oxygen-rich, which will produce better performance and fuel economy.
On a naturally aspirated engine, usually a cold air intake will be the superior choice because of the improved intake temperatures (IAT). However, on a turbo-diesel like the LB7 Duramax, intake temperatures are not nearly as important. This is because turbo-diesels have intercoolers located after the turbo, which cools down the turbocharged air.
This means that when picking out an intake, you should prioritize something that is going to deliver the best flow and the most volume. If you really want to improve cooling on your LB7 Duramax, investing in a larger intercooler is the best way to go.
Open vs Closed Airboxes
When picking out an LB7 cold air intake or short ram air intake, another decision you will be presented with is whether to get an open or closed intake. The stock Duramax LB7 intake comes with an airbox, and most aftermarket intakes have one, too. The purpose of an airbox is to seal off the filter from the engine bay to improve cooling and longevity. It shields the filter from the engine bay heat, and also stops it from accumulating as much dust and debris.
One downside is that many people claim that airboxes can impede airflow by adding a restriction on the filter’s ability to suck in air. In addition, they are also more expensive, as sometimes just the airbox can add as much as $100 to an intake kit. Also, on turbo-diesels like we mentioned, intake temperatures are not nearly as important as the intercooler. So you might be paying a significant amount extra for an airbox that doesn’t help with cooling.
Typically, we recommend using open box intakes, but airboxes can be beneficial, too. Besides price, there is not much of a downsize to them, other than sometimes fitment.
Dry vs Oiled Air Filters
The final decision you are presented with when choosing a Duramax LB7 cold air intake or short ram air intake, is whether or not to use an oiled filter. Typically, oiled filters are reusable and a little bit more expensive. They do a superior job of trapping dirt and debris due to the oil, and they flow just as well as dry filters.
However, oiled filters are notorious for fouling the mass airflow meter (MAF) or making it read incorrectly. Often, the oil will drip off of the filter media and make its way into the MAF, causing issues. We definitely recommend getting a dry filter. If you do choose to go oiled, then make sure you are careful when applying the oil and that you regularly check your MAF connection.
Benefits of Duramax LB7 Cold Air Intake Upgrade
The following are benefits of an LB7 cold air intake or short ram air intake upgrade:
- +5–15 horsepower
- +10–20 lb-ft of torque
- Increased fuel economy
- Increased engine sounds
- Increased throttle response
The most obvious benefit from installing a cold air intake is the performance increase. Due to the higher flowing nature of an aftermarket intake, you can usually see gains of 5–15 horsepower and 10–20 lb-ft of torque. You will see even more when combining an intake with a downpipe or tuning, which is usually the next step for most people.
In addition to having better performance, you’ll also notice the throttle response is better and your engine gets slightly better gas mileage. The difference is not drastic, but it is typically in the 0.5–1.5 mpg range.
Finally, you’ll also be able to hear your engine much more through an aftermarket intake. Not only does the larger filter make more noise, but even intakes with airboxes do not have the insulation the OEM intake does. It’ll be very obvious to you and everyone else in the car when you upgrade the intake, and most people enjoy the sound.
Best Duramax LB7 Cold Air Intakes
The top 3 Duramax LB7 performance intakes are:
- Banks Power Ram Air Intake
- S&B Cold AIr Intake
- Volant Cold Air Intake
There are dozens of LB7 cold air intakes and short ram intakes on the market, and these are the top three out of them all. These are widely considered by enthusiasts to be the best performance intakes for the LB7, and they all produce similar amounts of horsepower and torque. We recommend the Banks Power unit if you can afford them, but the S&B and Volant are also solid options. Let’s dig in!
1) Duramax Banks Power LB7 Ram Air Intake
First up on our list is the ultra-popular LB7 Banks Power Ram Air Intake. Banks Power have produced some very popular and powerful Duramax parts over the years, including for the LB7, and they are very respected within the community. It might sound a little surprising to be picking a ram air instead of cold air intake for the Duramax LB7, but this is one of the few cases where it makes sense.
The Banks Power LB7 intake is marketed as a ram air intake, but you’ll notice from the design that it locates the filter in the same place as all the LB7 cold air intakes. This means the Banks Power will deliver close to the same IATs as a cold air intake. It comes with an open airbox that hangs down in the engine bay, and is connected to a two-piece tubing system.
With the Banks Power, you can see maximum gains of 15 horsepower and 25 lb-ft of torque with tuning. The intake flows 57% better than the stock unit, and can be had with either an oiled or a dry air filter. If price is not a factor, the Banks Power LB7 intake is the best option.
2) Duramax S&B LB7 Cold Air Intake
The next intake on our list is the S&B LB7 Cold Air Intake. The S&B is one of the most popular LB7 cold air intake kits on the market, and S&B themselves are quite a reputable company. Not only are they known for their intake systems, but their air filters themselves are some of the most popular and widely used on the market. Many aftermarket intakes use S&B filters over K&N filters on turbo-diesels due to superior performance.
The S&B LB7 intake comes with either dry or oiled filters, and has an airbox with a closed lid. However, you can remove the lid if you choose to. The S&B has a similar design as the Banks Power, but the filter does not hang down and is visible due to the see-through cover. Compared with OEM, the S&B intake flows more than 42% better.
The S&B LB7 cold air intake is another one of the top choices on the market, and it is also CARB certified with its own EO number. That makes it a great choice for those in states with stricter emissions. It’s a little cheaper than the Banks Power intake and works about as well, and is an easy choice for second place.
3) Duramax Volant LB7 Cold Air Intake
The final intake we recommend is the Volant LB7 Cold Air Intake. Volant is another popular name in the intake industry, and they make a wide range of systems for many vehicles, including for more than just turbo-diesels.
The Volant LB7 cold air intake comes with an airbox and your choice of either a dry PowerCore filter or an oiled MaxFlow 5 filter. Both are high-velocity venturi filters that work exceptionally well. The Volant is designed very similarly to the S&B intake, but the top of the airbox is not see-through. Also like the S&B, the Volant intake is CARB certified with an EO number.
The Volant intake costs between the Banks Power and S&B intakes, and it performs about the same as either. Some people might prefer the S&B due to the see-through cover, but the Volant air box looks nice, too.
Duramax LB7 Cold Air Intake FAQ
A cold air intake is a great way to increase horsepower and torque and improves gas mileage. It is a very popular Duramax LB7 modification.
A Duramax LB7 cold air intake can add 5-15 horsepower and 10-25 lb-ft of torque. They are great LB7 upgrades that are easy to install.
The best Duramax LB7 cold air intake is the Banks Power ram air intake.
Yes, an LB7 cold air intake will increase horsepower and torque and improves gas mileage. It is a very popular Duramax LB7 modification.