The 7 Best Wideband Gauges of 2021

Whether it has a reflash or a standalone ECU engine, a wideband gauge is your most reliable tool when tuning a high-performance engine. This gauge reads the exhaust system's oxygen content using an oxygen sensor and shows you whether the engine is running rich or lean.
The unit reads and shows you wider air-fuel ratios results, which means you get more precise readings, enabling you to fine-tune the engine’s performance to get the best air-fuel mix.
That said, you need to have the best wideband gauge to achieve great tuning. This review showcases 7 of the best ones that you can get in the market.
7 Best Wideband Gauges – Review
IMAGE | PRODUCT | FEATURES | |
---|---|---|---|
![]() ![]() ![]() | 1. AEM 30-0300 X-Series (Best Overall) | ||
![]() ![]() ![]() | 2. AEM 30-4110 (Best Budget) | ||
![]() ![]() ![]() | 3. Innovate Motorsports 3918 MTX (Fastest) | ||
![]() ![]() ![]() | 4. Auto Meter 4379 (Best for Gas Engine) | ||
![]() ![]() ![]() | 5. GlowShift GS-TCD02W (Best Aftermarket) | ||
![]() ![]() ![]() | 6. AEM Display Set (Convenient Combo Set) | ||
![]() ![]() ![]() | 7. Innovate Motorsports 3873 DB (Easiest to Install) |
PRODUCT |
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1. AEM 30-0300 X-Series (Best Overall) ![]() ![]() ![]() |
2. AEM 30-4110 (Best Budget) ![]() ![]() ![]() |
3. Innovate Motorsports 3918 MTX (Fastest) ![]() ![]() ![]() |
4. Auto Meter 4379 (Best for Gas Engine) ![]() ![]() ![]() |
5. GlowShift GS-TCD02W (Best Aftermarket) ![]() ![]() ![]() |
6. AEM Display Set (Convenient Combo Set) ![]() ![]() ![]() |
7. Innovate Motorsports 3873 DB (Easiest to Install) ![]() ![]() ![]() |
1. Best Overall Wideband Gauge: AEM 30-0300 X-Series



Photo: AEM
- Sensor: Bosch LSU 4.9
- Range: 8 – 20 AFR
- Size: 2-1/16 inches
The AEM 30-0300 X-Series is our best overall model. It features patented X-Digital technology, which gives these controllers the capability to display values that other wideband gauges cannot.
For instance, this one has a much wider range of 8 – 20 AFR and can display these values to the hundredths of %.
Additionally, this technology results in a much faster response time, which improves the wideband feedback control, thereby enabling you to carry out a safer, robust, and more accurate tuning.
On the outside, the gauge has a visually striking faceplate and a 7-segment center display that is 87% larger than other AEM units, which makes it much easier to read.
Other features include compatibility to car electrical systems that run up to 16 volts, auto-dimming, and a wiring harness plus a weld-in stainless-steel bung in the kit.
However, the package will not include a boost pressure gauge. But, you can always get one separately if you do not already have one.
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2. Best Budget Wideband Gauge: AEM 30-4110



Photo: AEM
- Sensor: Bosch LSU 4.9
- Range: 10 – 20 AFR
- Size: 2-1/16 inches
The AEM 30-4110 wideband gauge is a more budget-friendly option for those that do not want to spend much. What makes it one of the best in the market is that it features the latest and most accurate Bosch LSU 4.9 sensor.
Additionally, the unit requires no free air sensor calibration as it is laboratory calibrated beforehand. It also gives a wider air-fuel ratio sensing range of 10 – 20 AFR on its digital display.
The gauge is inside a 2-1/16-inch (52mm) casing. This universal size ensures that it fits in most gauge pods for mounting anywhere inside the car.
Slight customization of the gauge’s design is also possible, with interchangeable black and white faceplates and interchangeable black and silver bezels, all of which are in the package.
Other features include a digital display with a .1 resolution, an outer bar graph with an LED needle, and a 0 – 5-volt analog output.
The included wiring harness is a bit short, but it should still be more than enough for most engines and is not a big deal.
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3. Fastest Wideband Gauge: Innovate Motorsports 3918 MTX



Photo: Innovate Motorsports
- Sensor: Bosch LSU 4.9
- Size: 2-1/16 inches
If you do not want to waste a lot of time waiting for readings, the Innovate Motorsports 3918 MTX is a perfect choice as it is one of the fastest wideband gauges on our list. This gauge provides a faster sensor frequency, and the analog output speed is also higher.
The unit comes with the top-performing Bosch LSU 4.9 oxygen sensor. It has an enhanced heater control for superior sensor performance in high-performance applications, such as in forced induction engines.
While doing this, a fast-analog output speed keeps the car’s ECU up to date with all air-fuel ratio changes in real-time for effective monitoring.
Other features include a large digital display in AFR or Lambda, a programmable digital needle, and a 52mm diameter gauge housing. Plus, it has interchangeable black and white faceplates and bezels.
However, calibration is necessary before use, but you will also get an instruction manual to help you with this, so it should not be a big concern.
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4. Best Wideband Gauge for Gas Engine: Auto Meter 4379



Photo: Auto Meter
- Sensor: Bosch LSU 4.2
- Range: 10 – 17 AFR
- Size: 2-1/16 inches
Auto Meter’s 4379 is the ideal choice for those that drive gasoline engine vehicles. But it still has broad compatibility with most street and race car electrical systems because it can operate in either 12 or 16 volts.
What's more, it has a digital segment display that shows the air-fuel ratio on a 10 – 17 range, with a resolution of 0.1. Combined with an external LED radial bar graph display, the kit gives you highly accurate readings and is easy to read.
The gauge also comes as a complete kit, including a Bosch LSU 4.2 oxygen sensor, 8-foot wiring harness, a weld-in stainless-steel bung, installation instructions, and mounting hardware for easy installation.
On the downside, the accompanying LSU 4.2 O2 sensor is not as good as the newer 4.9 model in the AEM 30-0300 X-Series, and its AFR range is not very wide. However, the unit still performs quite well and has a 0 – 4-volt data output feed for laptop tuning, ECU, or a data acquisition unit.
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5. Best Aftermarket Wideband Gauge: GlowShift GS-TCD02W



Photo: GlowShift
- Sensor: Bosch LSU 4.9
- Range: 10 – 20 AFR
- Size: 2-1/16 inches
For an aftermarket wideband gauge, the GlowShift GS-TCD02W is excellent as it has a lot to offer. One of this product's key highlights is the self-calibrating function that ensures the gauge is at optimal performance from the start.
The display is also fantastic because it will allow for easy reading even at a glance. Also, you get to choose the display color you prefer from 10 options.
The 10-foot sensors harness is longer than what many aftermarket gauges will give you. And for the sensor, this gauge uses the advanced and highly accurate 4.9 LSU wideband oxygen sensor.
Because the mounting hardware and instructions are part of the package, you can be sure of an easy time setting up this wideband gauge.
While this model could be a little faster, the speed is still higher than most other aftermarket ones within its class out there.
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6. Convenient Wideband Gauge Combo Set: AEM Display Set



Photo: AEM
- Sensor: Bosch LSU 4.9
- Range: 10 – 20 AFR
- Size: 2-1/16 inches
The AEM Display Set comes as a wideband gauge and a boost pressure gauge combo. Hence, you get the two important tools required for tuning your engine in one package.
The wideband gauge is quite impressive with its 10 – 20 AFR range, and it is supported by the pressure gauge’s -30 to 35 PSI range, which is ideal for both fuel injector and carburetor motors.
All have digital scales, with digital LED displays on the middle section and an outer LED needle, making the gauges easy to read. Also, you get a universal 52mm housing size, which can fit in most gauge pods.
Additionally, all of them come with interchangeable black and white faceplates, as well as black and silver bezels, which customize their looks to your preference.
While this is a little more expensive option, it should be obvious as it comes as a set with two handy tools in one. If you consider the cost of buying them separately, it is clear you still get a good deal with this combo set.
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7. Easiest Wideband Gauge to Install: Innovate Motorsports 3873 DB



Photo: Innovate Motorsports
- Sensor: LC-1
- Size: 2-1/16 inches
With the Innovate Motorsports 3873 DB, you can be sure of a hassle-free time when it comes to the installation as it has with everything you will need. Better still, the manufacturer also provides clear directions on what to do.
Besides the easy installation, you also do not have any issues reading the data as this unit comes with a bright and clear LED display with two color options: blue and red.
Another element that makes this a unique wideband gauge is the powerful LogWorks software. The software will allow for high-speed wideband data logging. And users can also add several sensor interfaces or log data for 5 main parameters directly to a PC.
The few drawbacks are that this is a vehicle-specific gauge, and it may need recalibration before use. Recalibration is quite simple, and provided you have a compatible vehicle, you should not have any issues.
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How to Buy the Best Wideband Gauge



1. Compatibility
A wideband gauge can only be useful if it is compatible with the type of engine that runs your car, which has to do with two things.
First is the electrical system. Not all cars have the same voltage system. Some have as high as 20 volts running through the electrical wires around the engine, while others only handle 12 volts.
This difference means that you must look for a wideband gauge that will work well at the specific voltage running through your car’s electrical system without being over or underpowered.
The other issue to do with compatibility is on fuel type. Some units like Auto Meter’s 4379 are designed for gasoline engines only, while others can work in different fuel engine types. Make sure you check on this and buy the wideband gauge that matches your engine’s fuel type.
2. AFR Monitoring
You can still install an oxygen sensor in your engine’s exhaust system without the wideband gauge, but this won’t be very helpful.
You need to match the sensor with a compatible gauge to read the air-fuel mix information and pass this data to the ECU for analysis.
For this kind of effective AFR monitoring, you will need a wideband gauge to measure the ratios you are running. For instance, if your engine runs lower than 10 AFR, then the AEM 30-0300 X-Series would work best as it goes down up to 8 AFR.
3. Accuracy and Performance
Whichever wideband gauge you decide to buy, you should not compromise on accuracy and performance. While there is no reliable way of determining the wideband gauge's accuracy, at least ensure that the included sensor performs exceptionally well, such as the LSU 4.9.
With a good sensor in the bag, the next thing is that there should be very little or no delay at all between the actual measurement and displaying the results on the gauge.
Ideally, this lag should not be more than half a second because if the transmission delays much further, the results will not be received on time, leading to imprecise engine recalibration or tuning.
4. Durability
For every product you buy, durability is always a vital factor to consider, and for a wideband gauge, this is no different.
There is a possibility of dropping the unit during the installation process. If it is not rugged enough, some components might break.
Apart from the gauge itself, also make sure that the included accessories such as the mounting hardware and bungs are sturdy so that the entire setup lasts for a long time once installed.
Conclusion
Wideband gauges are essential components in engine performance tuning for drivers who want to improve the air-fuel ratio in the combustion chambers for efficiency and max output. And now, finding the best wideband gauge should be a breeze.
However, to make it even easier to choose one from our list, the AEM 30-0300 X-Series is our best overall, thanks to the advanced X-Digital technology and broad AFR range.
But, if you are on a tight budget, the more affordable AEM 30-4110 is perfect. This model also includes the highly accurate Bosch LSU 4.9 sensor.
- 7 Best Wideband Gauges – Review
- 1. Best Overall Wideband Gauge: AEM 30-0300 X-Series
- 2. Best Budget Wideband Gauge: AEM 30-4110
- 3. Fastest Wideband Gauge: Innovate Motorsports 3918 MTX
- 4. Best Wideband Gauge for Gas Engine: Auto Meter 4379
- 5. Best Aftermarket Wideband Gauge: GlowShift GS-TCD02W
- 6. Convenient Wideband Gauge Combo Set: AEM Display Set
- 7. Easiest Wideband Gauge to Install: Innovate Motorsports 3873 DB
- How to Buy the Best Wideband Gauge
- Conclusion