When AEM released its first wideband air-fuel-ratio gauge, just a little more than a decade ago, car tuning was beginning to emerge as the best way to maximize performance from your engine. AEM, which stands for Advanced Engine Management, had been tuning cars for more than 10 years before that, so it recognized the need.

At the time, about the only place you could find a wideband setup for measuring AFR in a vehicle’s exhaust system, was at a dynamometer facility geared for performance tuning. AEM had just launched a single and dual wideband controller and thought, why not put the controller in the gauge? At the time, AEM didn’t make gauges, but it took the initiative and built one — and then sold a gazillion of them to racers and performance enthusiasts the world over.

“We thought it was a great idea to be able to see your air-fuel ratio, and it was kind of an afterthought. Since then it’s arguably become one of the best selling products in performance and racing because of what it provides,” said AEM’s director of marketing and PR Lawson Mollica. “We took something that was thousands of dollars and a rarity, basically only seen at dyno shops, and made it available to racers to put in their racecars and have access to it for a couple of hundred bucks.”

30-0300-angle_web

Now, AEM has developed a new wideband air-fuel-ratio sensor controller gauge and it’s just hitting the market now. The new X series wideband controller features a new a single-board design with 100 percent digital technology, which provides a blisteringly fast response rate — fewer than 20 milliseconds.

With analog-style widebands, the signals are typically filtered to reduce noise and other irregularities, but filters also slow down the response time and smooth out the signal. They still provide an accurate air-fuel reading, but they miss the finer details. The new X series doesn’t miss anything, including transitional conditions like tip-in and on-off throttle, not to mention irregularities such as momentary lean conditions or misfires, and if it’s connected to AEM’s AQ-1 logger or its Infinity ECU, all those anomalies are recorded so you can diagnose and repair those conditions.

“When we looked at updating our technology, because we pioneered this concept of a wideband gauge you can have in your vehicle, it couldn’t just be better than what we had made,” Mollica said. “It had to be the best on the market, so that was our target, and it was a very, very hard target.”

The new gauge still measures 2 1/16 inches in diameter, but it’s much thinner than the first generation gauge, which opens more options for mounting. The digital display is 87 percent larger for greater legibility in race conditions. It also has mode and select buttons on its face to allow for displaying AFR, lambda and O2 percentage. It even displays out to three digits behind the decimal point if you want.

The new X series controller gauge uses the latest Bosch sensor, which is calibrated from the factory, but it also gives the user the ability to “free air” calibrate it if necessary. It’s simple to do, Mollica said, using the buttons on the gauge face.

“It’s just an amazing little gauge and we’re really excited about it,” he said. “It takes what we pioneered over a decade ago and really resets the bar for this type of technology.”

As you will see in the photos below, installation of the X series as a standalone gauge is every bit as easy as the previous generation. We asked to follow NASA SoCal racer James Brown’s installation on his Spec Miata.

RESOURCES

http://www.aemelectronics.com

The downpipe on a 1999 Mazda Miata has a heat shield clamped around it. Brown cut the shield with one hole saw and the opening in the pipe for the bung with another.
The downpipe on a 1999 Mazda Miata has a heat shield clamped around it. Brown cut the shield with one hole saw and the opening in the pipe for the bung with another.
The bung in this shot is fitted in place, but has yet to be welded in.
The bung in this shot is fitted in place, but has yet to be welded in.
The gauge is the same size as the previous generation, but its digital display is 87 percent larger and there are mode and select buttons for controlling the X series’ many functions.
The gauge is the same size as the previous generation, but its digital display is 87 percent larger and there are mode and select buttons for controlling the X series’ many functions.
A thinner gauge and simple connections make the new X series just as easy to install as the previous generation.
A thinner gauge and simple connections make the new X series just as easy to install as the previous generation.
Conveniently, 2 1/16 gauges slip neatly into the air conditioning outlets on Miatas, providing a great spot for the driver to check the gauge quickly on straightaways.
Conveniently, 2 1/16 gauges slip neatly into the air conditioning outlets on Miatas, providing a great spot for the driver to check the gauge quickly on straightaways.
Brown installed a Powerwerks six-pole bus to power the AFR controller gauge and other accessories. The fuse shown is 15 amps. It should be a 7.5.
Brown installed a Powerwerks six-pole bus to power the AFR controller gauge and other accessories. The fuse shown is 15 amps. It should be a 7.5.
Brown routed the wiring along with the harness for the factory O2 sensor then ran the AEM harness through a factory opening in the firewall on the driver’s side.
Brown routed the wiring along with the harness for the factory O2 sensor then ran the AEM harness through a factory opening in the firewall on the driver’s side.
The installation is so simple considering how much capability is in one gauge. Screw the O2 sensor into the exhaust pipe and connect its harness to the gauge. Connect the gauge to power for a standalone unit or wire the harness into a logger for even more data.
The installation is so simple considering how much capability is in one gauge. Screw the O2 sensor into the exhaust pipe and connect its harness to the gauge. Connect the gauge to power for a standalone unit or wire the harness into a logger for even more data.
The sensor is heated, so upon starting the car cold, the gauge tells you the sensor is heating up to operating temperature.
The sensor is heated, so upon starting the car cold, the gauge tells you the sensor is heating up to operating temperature.
The digital display is 87 percent larger than the older model and displays out to three places after the decimal point if you like.
The digital display is 87 percent larger than the older model and displays out to three places after the decimal point if you like.
The mounting position of the AEM sensor points it up into the transmission tunnel out of harm’s way.
The mounting position of the AEM sensor points it up into the transmission tunnel out of harm’s way.
Of course, the AFR controller gauge kit comes with a sticker, which also makes the car faster.
Of course, the AFR controller gauge kit comes with a sticker, which also makes the car faster.
Comments
Image courtesy of Brett Becker