The 5 Best Honda Civic 1.5T Upgrading Options. Honda 1.5T engines are also known as 1.5 Turbo engines and L15 VTEC or VTC engines. The 1.5L inline-4 engine in the Honda Civic Si produces up to 205 horsepower and 192 lb-ft of torque. It’s an impressive performance for such a small engine. The 1.5T, on the other hand, leaves plenty of room for more power. Turbo designs enable excellent power gains with a few simple modifications. This guide will go over some of the best Honda 1.5T upgrades, including power gains, benefits, cost, and more.
*The L15 Turbo engines are available in a variety of engine codes. The L15B7 in the Honda Civic and Civic Si is our primary focus. However, much of this information applies to all turbo 1.5L Honda engines, including those found in the CR-V and Accord. Fitment and exact results vary, but these are still fantastic mods for those engines.
L15 1.5 Turbo Background Information
As briefly stated above, many of the modifications and general information in this article apply to all Honda L15 1.5 Turbo engines. This engine family is used in a variety of engine variants and models. As a result, fitment and exact results from each mod may differ. Regardless, the top 5 Honda 1.5T upgrades are applicable to nearly all of these engines.
All of these engines are based on the same basic design and have a 1.5L displacement. Honda employs so many engine codes that it can be confusing. The differences between the engines, however, are minor.
Variants of the Honda L15 1.5T Engine
Please bear with us as we break down some basic information about each of the 1.5T engine variants. If you’re not interested in this information, skip down to the best Honda 1.5T upgrades section. The L15 turbo engine comes in 11 variations, but we’ll focus on the most common 1.5T engines.
Anyway, let’s get started on the L15 turbo engines. We’re looking at the fundamentals here, such as which years and models use which engines, power output, and so on. Following that, we’ll go over the top 5 bolt-on engine upgrades for the Honda 1.5 Turbo.
VTEC Turbo L15B7
What vehicles are powered by the Honda L15B7 1.5 turbo engine? It is in the years and models listed below:
- Honda Civic Turbo (2016-2021)
- 2017-2021 Si Honda Civic
- Honda Vezel 2019, 2020, and 2021
- Honda XR-V from 2020 to the present
In standard Civic models, the L15B7 produces 174hp and 162 lb-ft of torque with 16.5 pounds of boost. The engine in the Civic Si produces 205hp and 192 lb-ft of torque while operating at 20.3 psi. It should be noted that the Civic Hatchback does NOT use this engine. Instead, Hatchback models receive the L15BA VTC Turbo engine, which will be discussed further below.
This engine is a primary focus of this article. Another point to consider is that horsepower gains may be greater in base Civic Turbo models. Because it runs higher boost, the Si has more power from the factory. In other words, the standard Civic engine is just as capable, but it has a lower starting point, resulting in larger power gains.
Turbo L15B7 VTC
Variable timing control on the intake and exhaust is added to VTC engines. VTEC is still present on the exhaust side. This L15B7 VTC engine is found in the following vehicles:
- Honda Civic 2022+
It also has the same 16.5psi peak as the previous VTEC version in Civics from 2016 to 2021. The engine produces 180hp and 177 lb-ft of torque. A solid 6 horsepower increase and an even more impressive 15 pound-feet increase.
L15BA Turbo VTC
The Honda L15BA engines are essentially the same as the L15B7 engines found in the Civic and Civic Si. However, for some strange reason, it employs thinner connecting rods. Your guess is as good as ours as to why this engine has its own engine code. It is available in the following Honda models:
Honda Civic Hatchback (2016-present)
When equipped with the 6-speed manual transmission, it produces the same 180hp and 177 lb-ft. With the CVT transmission, power remains constant, but torque drops to 162 lb-ft.
L15BE Turbo VTC
Following that is the L15BE VTC engine found in the following CR-V models:
- Honda CR-V from 2017 to the present
The boost pressure is around 18.5psi, and the power output is a good compromise between the base Civic and Si models. It has 190hp and 179 lb-ft of torque.
Turbo L15BE VTEC
The L15BE VTEC engine is the last on our list. This Honda 1.5T engine can be found in the following models:
- Honda Accord (2018+)
It’s one of the more powerful factory variants, with 192hp and 192 lb-ft. The Honda Civic Si has less horsepower, but it has the same peak torque and a similar boost of 20.2psi.
Honda 1.5T Upgrades That Work
Okay, that covers the majority of the fundamentals. As a result, it’s time to get into the best Honda 1.5T upgrades and aftermarket modifications. There are numerous options, so where do you even begin? What 1.5 turbo mods provide the most bang for your buck? These are just a few of the issues addressed in this article.
To begin, some of the best Honda 1.5 turbo engine mods are:
- Downpipe (exhaust) (exhaust)
- WMI / Combustion
The above 1.5T upgrades are discussed in detail throughout the rest of this article. They’re among the best basic bolt-on modifications for the 1.5L inline-4 turbo engine. It’s a good starting point before moving on to more serious upgrades like a turbo upgrade.
*Please keep in mind that any power gains or specific data are estimates. Actual results may differ depending on a variety of external factors. Some of the 1.5 turbo mods on this list may be unlawful in some or all states. They are only meant for off-road use.
1) Honda 1.5 Turbo Tuning and Tunes
Looking for a single Civic 1.5T modification? If that’s the case, a song is without a doubt the best place to start. Tuning not only provides massive horsepower gains, but it also serves as the foundation for building more power. A tune is required to maximize the performance gains from other mods such as an intake, downpipe, and so on.
The following are some of the advantages of running a tune on the Honda 1.5 turbo:
- Gains of 20-40+whp
- Gains of 20-40%+ wtq
- Improved fuel economy
- Monitoring and data logging
There are numerous amazing features and benefits that come with the right tune. Gains of 20-40 hp and torque to the wheels are already impressive. You may notice improved fuel economy with proper tuning and driving. That is unlikely to be the case if you use your newfound power.
Otherwise, some tunes support data logging and monitoring. It’s nice to be able to see and understand what’s going on with the engine. Codes can be easily read and cleared, and the list goes on.
Tunes for the Honda Civic 1.5T
We normally include a few options, but we can’t bring ourselves to do so here. Burger Motorsports provides an incredible JB4 piggyback tune for the Honda 1.5T engine. They began developing tunes in the BMW world shortly before 2010, when BMW began building turbo engines. We have had great success with the JB4 on all of our BMWs.
Piggybacks are not the same as standard flash tunes. That’s a discussion for another time, but these songs offer so much in such a small package. The JB4 is a simple plug-and-play installation that includes 9 different tuning maps. In a matter of seconds, you can go from stock to mildly tuned to full kill mode. There is no need to pause and re-flash the entire ECU.
They also provide a few maps that are compatible with 30% E85 blends. We’ll go over this further later, but E85 blends have a lot of potential. The list of features is endless, so be sure to check out the JB4. There isn’t a single better Honda 1.5T upgrade for the price.
2) Honda 1.5T Performance Intake Upgrades
This list is in no particular order, but our second favorite mod is an intake. No, a Civic 1.5T intake upgrade isn’t as capable as the other Civic 1.5T upgrades on the list. However, because it is simple to install and inexpensive, it is an excellent mod to pair with a tune. It’s critical to improve airflow into the engine as you increase power and boost. A 1.5 turbo intake system comes into play here. Among the advantages are:
- Comparable torque
- Fantastic turbo sounds
- Improved response / turbo spool
Again, the benefits of an intake aren’t particularly impressive. However, it is still a fantastic upgrade for a variety of reasons. Honda Civic 1.5T intake mods enable a plethora of fantastic turbo and induction sounds. We believe it is highly addictive and would recommend trying it just for the sounds. Additionally, intakes can improve engine response and turbo spool. Just a few additions to an already excellent mod in terms of power gains and sounds.
There are numerous names for performance intakes. Upgraded intake system, cone intakes, air-box upgrades, cold air intakes, and so on. In our opinion, the primary distinction to be made is between open and closed intakes.
Upgrades for Open vs. Closed Intakes
An open intake lacks an air-box that surrounds the air filter. A closed system, as the name implies, retains an air-box to keep the filter covered in a housing. We love open intake systems on turbo engines and refuse to use anything else in our cars. But what about intake temperatures and heat soak? Isn’t pulling in warm air going to hurt the performance of the Civic 1.5T?
Good questions. This is especially true for naturally aspirated engines or forced induction engines without an intercooler. The Civic 1.5 Turbo engine, on the other hand, employs an intercooler. The air is superheated as it passes through the turbo, where it is cooled by the FMIC. Temperatures at the intake have little to no effect on the ability of the intercooler to cool the pressurized air.
However, open intake upgrades have the fewest restrictions. They will provide the best airflow and sound. Running an open intake system, such as this one from BMS, is, in our opinion, the obvious choice. We use BMS open intakes on all of our BMW engines, just like the JB4.
3) Civic 1.5L Turbo Downpipe Modifications
A downpipe (DP) is likely the second best bolt-on mod in terms of horsepower and torque. They are without a doubt one of our favorite turbo engine mods. This is also true for the Honda Civic 1.5 Turbo engine. The downpipe bolts directly to the turbo, making it the most important post-turbo exhaust component.
Stock Civic downpipes are great for emissions but severely degrade performance. Back pressure is created by the restrictive cat, which slows turbo spool and limits maximum performance. Reducing back pressure with Honda 1.5T upgraded downpipes has numerous advantages:
- Improved turbo spool
- Fantastic sounds
- Reduced EGTs
- Back-pressure reduction is beneficial to engines.
It is a lengthy list. Not only does a downpipe increase power and torque, but it also allows for faster turbo spool. This means significantly more low-end torque. You can also feel a slight push back in your seat.
Combine that with a more aggressive but not overpowering exhaust note. Cold starts or heavy throttle inputs produce the most DP sounds. Otherwise, less back-pressure helps to reduce temperatures and is better for the engine and turbo in general.
Catless Civic 1.5 vs High-Flow DP
All of these advantages must have a significant drawback, right? Unfortunately, this is the case with Honda 1.5T downpipe upgrades. The goal is to alleviate as much back pressure as possible. This requires the removal of the catalytic converter, which is not street legal. Emissions from passing vehicles can be a problem.
In come high-flow downpipes. A high-flowing catalytic converter is retained in these Civic 1.5 Turbo downpipes. They may still be illegal, but they are more likely to emit emissions. The power gains aren’t as dramatic as with a catless downpipe, and cats are expensive. But it’s still a fantastic mod.
L15 1.5T Downpipe Upgrades That Work
When it comes to quality, those who choose a catless downpipe don’t have to think too hard. What matters with a downpipe is that it is made of stainless steel for longevity and that it fits properly. Otherwise, it’s just a plain steel pipe. The point is, don’t be concerned about quality as long as the downpipe is made of rust-free materials and fits properly.
4) FMIC Honda 1.5 Turbo
The intercooler is a critical component of any forced induction engine. Turbos, for example, are powered by hot exhaust gases. As air is compressed, it also heats up. When the two are combined, the charge air exiting the turbo is HOT. Obviously, this is not good for engine performance or safety. That’s why an intercooler comes standard.
On stock boost, the Honda 1.5 Turbo factory FMIC performs admirably. When you start adding more power and boost, it quickly becomes overwhelmed. The following are the advantages of Honda 1.5T upgrades to the front mount intercooler:
- IATs with lower temperatures
- Performance that is consistent
- Engine protection
FMIC upgrades aren’t particularly powerful. Most setups will produce about 5whp, but more power is possible. An intercooler mod, on the other hand, goes a long way toward ensuring consistent performance. Have you ever noticed how sluggish your car feels after a few punches? That’s heat soak in action. It causes the engine’s timing, boost, and overall power to pull. As a result, an FMIC upgrade could save the engine 10-20whp.
Reduced IATs assist the L15 1.5L engine in maintaining performance even after multiple back-to-back pulls. Cooler air also reduces the possibility of engine pre-detonation, which is a major cause of blown motors. Overall, don’t expect massive peak performance gains, but this is still a very worthwhile mod.
Related : The Honda Civic Coilovers at Their Finest
The Top 1.5T FMIC Mods
An air-to-air front-mount intercooler is used in Civic 1.5 Turbo engines. Outside air passes through fins in the intercooler to cool the charge air, which is mounted at the front of the vehicle. FMIC upgrades must consider both volume and surface area. In general, greater surface area and volume imply greater cooling capacity.
There are numerous excellent options, but we do not recommend price shopping on FMICs. It is critical to locate a high-quality intercooler that maximizes cooling performance. Two Step Performance, PRL Motorsports, and Injen are all excellent choices.
5) Civic 1.5T Performance Enhancements – Fueling / WMI
Fueling improvements and water-methanol injection are extensive topics, as are 1.5T upgrades. We will undoubtedly address this in a separate post in the future. When it comes to increasing performance, however, high octane and high-quality fueling is essential. E85 blends are an excellent option, and some tunes, such as the JB4, allow for 30% E85 mixes with no other modifications.
The advantages of E85 are numerous. It has a 108 octane rating and helps the engine run cooler internally by reducing the risk of detonation. Even with a low E85 blend, power gains can be massive. The disadvantage is that E85 is less fuel efficient and puts more strain on the fuel system.
WMI provides similar benefits but reduces demand on the fuel system. It also significantly reduces intake temperatures. We don’t recommend starting with E85 or WMI because they are more advanced. Start with the basic Civic 1.5T upgrades and work your way up to more serious modifications like fueling and water-methanol injection.
Price: E85 costs the same as lower-grade fuels. WMI typically charges $300-500+ for the complete kit.
Other Honda 1.5 Turbo Mods & Complementary Mods
We’ve already written far more in this article than we intended. As a result, we’ll keep things brief in this section. Stay tuned for new content in the near future. Many of these additional mods will be covered in separate posts below. Anyway, here are a few extra power mods to think about:
- Turbo enhancements
- Fuel enhancements
You may also want to consider any supporting mods. More power equates to more heat. It also implies that you should think about traction, braking, suspension, and other factors. The main subject is CVT transmissions.
Honda CVT Transmission Modifications
Some CVT transmissions begin to have issues around 220-240 wtq. It is not a perfect science to predict when the transmission will have problems with increased torque. However, it is something to think about. There are CVT cooler upgrades that may help support the increased power and torque.
Summary of the Best Civic 1.5T Upgrades
The Honda Civic 1.5 Turbo performs admirably for its size. It’s also an efficient engine with a high level of dependability. Some, on the other hand, are always looking for more power and performance. The turbo design of the 1.5L inline-4 provides plenty of power. A few simple Honda 1.5T upgrades can elevate the engine to new heights.
The best single mod and starting point for the Civic Turbo is usually tuning. It provides the most bang for your buck while also maximizing power gains from other mods. A good mod to pair with a tune is an intake. If you still want more power, it’s time to upgrade to the Civic 1.5T downpipe and FMIC. Fueling mods provide even more power, but they are generally something to save for last.
When these simple bolt-on modifications are combined, the Honda L15 Turbo engines can gain up to 50-70whp. That’s quite impressive for a 1.5L engine. The CVT transmission is a major source of concern, so be cautious with torque or consider transmission upgrades. Finally, have fun with your mods!
What’s your take on Honda 1.5T upgrades? Are you thinking about any?