Installing an MTX-L PLUS Air/Fuel Ratio Gauge in a 1,000 HP Turbo SC300

Monitoring engine operating conditions in a 1,000+ HP engine is critical. Check out how the Innovate MTX-L PLUS makes it easy to monitor your air/fuel ratio.

For any engine to reach its maximum potential the fuel must burn efficiently. Running rich or lean is not good for performance, and in extreme cases it can be catastrophic. A rich engine is likely to be sluggish—excessive richness can even burn your exhaust valves. A lean engine is worse—it will be prone to piston-holin’ engine-killing detonation.

Originally featured in Super Street.

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An accurate reading gives you assurance that your engine is running to specifications.

In reality, it’s important to have a proper tune along with ability to accurately monitor the running condition any time you take a vehicle past stock. So as soon as you modify your engine, consider installing an air/fuel ratio gauge.

Sadly, we’ve seen enthusiasts spend countless dollars and waste countless hours experimenting with haphazard keystrokes as they try to ascertain lean versus rich conditions. Reading plugs, using EGT, or even going off your time slip just isn’t the most modern or effective way to tune. The good news is for around $200.00 you can wire up Innovate Motorsports’ new MTX-L PLUS wideband oxygen sensor and gauge kit and instantly putting the necessary information your finger tips.

To learn more about the MTX-L PLUS, click here.

Motorsports’ MTX-L PLUS gauge kit
Innovate Motorsports’ MTX-L PLUS gauge kit comes complete with everything for installation. All you’ll need is a pod to mount the gauge.

It’s actually amazing how that simple gauge can give you piece of mind. But there’s really nothing that compares to knowing that your tune is spot on when you mash the gas. Or, that something is amiss so you have a measure of protection to warn you before the rods come out of the block. That’s important to any enthusiast, whether you’ve simply added a cold-air kit to your stocker, or if you’re rolling with 1,200 ponies and 40 psi of boost.

Innovate’s MTX-L PLUS wideband kit makes it easy for any vehicle owner to affordably gather this important information. Whether you’re swapping jets or using the most advanced aftermarket EFI, the MTX-L PLUS will give you the 411 on your air/fuel ratio. And it will do it fast. The system incorporates the patented DirectDigital technology that’s combined with Innovate’s all-new Advanced Sensor Control to provide enhanced feedback from the sensor and to optimize heater control. And in addition to giving you a modern changeable look, the gauge kit also has a host of useable features.

MTX-L PLUS gauge MTX-L PLUS gauge

One of the many features is the removable faceplate and bezel. The kit comes with black and white faceplates and silver and black bezels.

The MTX-L PLUS gauge measures 52mm or 1 1/16-inch so it fits in standard gauge pods. It has an easy-to-read digital display with a sweeping “digital needle” around the diameter of the face and the display can show either air/fuel ratio or Lambda. Information comes from the Bosch LSU 4.9 wideband O2 sensor that is reliable and accurate. Additionally, the sensor can operate with a multitude of fuel types, and it’s user calibrated so it will remain deadly accuracy over time.

Bosch LSU 4.9 wideband O2
While the digital gauge takes center stage, the Bosch LSU 4.9 wideband O2 sensor is underneath doing the dirty work.

The “PLUS” version of the gauge is enhanced with faster Sensor Frequency for faster O2 sensor feedback, and faster Analog Output Speed, which helps ensure that your ECU sees changes in air/fuel ratio as they happen. Innovate has also improved the Heater Control function for superior sensor performance in forced induction and other high performance applications.

We dropped by Coastal Chassis Dyno in Tampa, Florida where owner Sam Lippencott was installing a MTX-L PLUS gauge kit on a highly modified 1997 Lexus SC300. This SC is packing a built 2JZ 3.0-liter powerplant boosted by a 80mm turbocharger, aftermarket intercooler, Virtual Works intake manifold, Full Race header and, for good measure, a 200-shot of Pro Flow nitrous. The beast was kicking out 1,070 RWHP at 40 psi and has run 10.40s at over 150 mph on drag radials.

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The fully modded J2Z sports a sizeable 80mm turbo and a 200hp shot of nitrous for good measure.

At this insane power level, Lippencott wanted deadly reliable air/fuel ratio feedback so he installed an MTX-L PLUS. Lippencott uses both a dyno and street driving for proper tuning and he’s had great success with MTX-L gauges in the past to record air/fuel on the dyno and under real-world driving and racing conditions.

“Innovate products are easy to install and are super reliable,” Lippencott told us. “I’ve relied on Innovate wideband gauges for years and I like that the MTX-L PLUS has excellent capabilities and offers options like the changeable faceplates and bezels. The customers really like that.”

MTS serial
The MTX-L PLUS comes with a MTS serial in/out for use with MTS enabled devices. Datalog using LogWorks software on your PC.

Innovate has smartly designed the kit with what it called MTS or Modular Tuning System so it can work in conjunction with a variety of devices. Using the serial “In” and “Out” wiring, you can connect directly data-logging units or to a laptop. Examples include the Innovate SSI-4, which records RPM, TPS, driveshaft rpm and MAP, and/or the PL-1 Pocket Logger. Or you can connect an MTX-Boost/Shift gauge and/or PL-1.

Like with any install, we recommend opening the supplied user manual to familiarize yourself with the gauge, it’s functions, and the installation procedure. In addition to wiring the unit properly, the guide covers best procedures for oxygen sensor placement and sensor calibration. These are two items that are critical to proper operation and reading.

Bosch sensor in a Lexus lambda sensor

(Left) The Lexus was fitted with a modified exhaust and already had a bung welded in place. We simply removed the plug and installed the Bosch sensor. (Right) The lambda sensor should be installed at a point permitting the measurement of a representative exhaust-gas mixture, which does not exceed the maximum permissible temperature.

Our Lexus already had a bung fitted to the exhaust system for the oxygen sensor, so our installation was simplified. We raised the car on a hoist, installed the Bosch sensor and ran the cable to the gauge. We then wired and installed the gauge, and finally we ran through the calibration procedure. Total install time was about an hour.

The MTX-L PLUS provides a modern look that is customizable, but more importantly, lets you keep an eye on air/fuel ratio under all driving conditions. The MTX-L PLUS also includes wiring for the aforementioned digital input/output, and two fully programmable analog outputs. This allows you to easily interface when dyno testing or using aftermarket data-logging. It also makes it easy to connect to aftermarket EFI systems and/or gauges. And, the sensor is versatile so can be calibrated to operate using a variety of fuels including gasoline, diesel, methanol, E85 or even propane.

Gauges in this Lexus
Gauges in this Lexus are hidden in the glove box.

Lastly, be sure to take advantage of the features, including Innovate Motorsports’ Logworks 3 software package. This is an invaluable tool that can streamline the tuning process for beginners and pros.

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