Total Control: Installing A Nitrous Outlet ProMax Controller

Nitrous oxide, that magical gas that creates massive amounts of horsepower from seemingly nowhere, has been used with internal combustion engines on vehicles since the late 1950s. In the early years, it was known to make massive power and massive messes on drag strips, while engines and drivetrains spectacularly suffered the result of “a bit too much gas.” 

It took many years to fine-tune the exact mixture of N20 and air/fuel to keep engines together while crushing record-breaking passes down the drag strip. However, as technology has improved, the safety of using nitrous has increased, which is where Nitrous Outlet comes into play. They have created easily adjustable electronic controllers that allow people to use nitrous to its full advantage with far less risk of instantaneously disassembling their engines.

Controlling The Chaos With A ProMax Controller

When running nitrous, the bigger the jet, the greater the chance of mechanical injury with the engine. Part of the solution for both power and safety is getting the air/fuel ratio just right. This is far easier to achieve in a wet system, where you have full control over both the amount of nitrous and supplemental fuel being injected into the engine.  

Another potential pitfall of a nitrous system is the sudden increase of power, which can be problematic for traction or vehicle control. To work through some of these issues with control, Nitrous Outlet has created an electronic controller to solve these problems. 

Nitrous Outlet’s flagship nitrous controller, the ProMax, has all of the bells and whistles, giving the end-user total authority over the nitrous system. We had the chance to hang out in the shop while the crew at Nitrous Outlet installed twin nitrous bottles and their ProMax Controller into a gorgeous blue C8 Chevrolet Corvette.

The ProMax Control has the ability to be programmed by the included touch screen or a laptop and the user can also easily switch between five different saved tunes. The ProMax is dual-stage capable, and is configurable from one to twelve-cylinder applications. It can also make closed-loop fuel adjustments based on wideband oxygen sensor input, has built-in 70-amp solenoid drivers, and built-in data logging.

Power Management

Nitrous Outlet’s ProMax Controller comes with a lot of power management adjustability, since that’s specifically what it was designed for. The ProMax Controller can exert control in various ways. Delay Activation delays nitrous system activation based on a programmed amount of time. In addition, it can enable gear lock out, which prevents the nitrous system from activating until a programmed amount of gear changes have been reached.

Time Based Progressive Ramp

The time-based setting on the ProMax ramps the nitrous in over a pre-programmed amount of time. For example, start at 30-percent nitrous and then ramp to 100-percent nitrous within 3.0 seconds. You can also set up an RPM-based progressive ramp, which ramps the nitrous in (or out) based on a programmed RPM curve. For example, at 3,000 rpm, the ramp starts at 25-percent, and then by 6,500 rpm, you’re at 100-percent nitrous flow.

The Nitrous Outlet switch panel and ProMax display screen fit nicely in the center console of a C8 Corvette.

MAP Based Progressive Ramp

The ProMax can also use manifold air pressure (MAP) to ramp the nitrous in or out based on boost pressure. Instead of the basic Wide Open Throttle switch activating the system, the ProMax Controller has a Throttle Position Sensor (TPS) based progressive ramp which ramps the nitrous in or out based on a programmed throttle position versus nitrous percentage. 

Speed Based Progressive Ramp

And if you need more tuneability, Nitrous Outlet even incorporates a progressive ramp based on vehicle speed. This setting uses wheel speed to ramp the nitrous in or out based on a programmed curve.

Safety Management

We all know nitrous oxide has the potential to harm engines when not used properly. Fortunately, the Nitrous Outlet ProMax controller has a number of adjustable safety settings integrated into the controller.

The ProMax Controller uses this intuitive screen to set parameters and “windows” for activation and deactivation of nitrous to make your life easier while driving and to save your engine from damage.

Lean and Rich Air/Fuel Cut Off

The Air-Fuel Ratio-based cutoff is one of ProMax’s most important safety features. When the air/fuel ratio is outside the programmed range of values, it will automatically turn the nitrous system off. There is also a fuel pressure loss cutoff which will deactivate the nitrous when the fuel pressure drops below the programmed value. 

Additionally, a nitrous pressure-based cutoff engages if the nitrous system is lower or higher than the programmed value. A Manifold Absolute Pressure cutoff will deactivate the nitrous system when a programmed vacuum or pressure value is outside of the preset window.

C8 Corvette Install

This, folks, is a frunk. Yes, a front trunk. If you own a car with a frunk, chances are you have done well in the stock market (think Ferrari, McLaren, or Lamborghini). The new C8 Chevrolet Corvette, with its engine in the rear, also has a frunk (for a lot less money than a McLaren). And this space looks like the perfect place to drop some nitrous bottles.

For the C8 Corvette installation, Nitrous Outlet brought out the big guns, including twin nitrous tanks in the frunk, their ProMax Controller, and a C8-specific wiring harness. This kit will wire up any 2020 and newer C8 Corvette with the LT2 engine. The installation instructions were easy to follow and included photos for those of us who hate to read.

If you have ever wondered where the fuse box is on a C8 Corvette, most owners will lean their elbows into it. It is right in-between and to the rear of the front seats. The ProMax Controller’s C8 wiring harness easily plugs into the stock fuse box for power.

A fair number of panels have to be removed from the C8 to get this project completed, but most of the panels are held in with screws versus clips. Which means you won’t break a bunch of clips during the process. In addition, the guys found access to the fuse panel between the seats.

The assembly instructions for the ProMax are pretty simple, but nothing is simple about drilling a hole into a brand-new Corvette.

The ProMax controller will be installed in the center console, allowing easy access to adjust nitrous injection parameters. It does require a few holes to be drilled, which isn’t for the faint of heart with a brand new $100,000 car. However, if the Nitrous Outlet instructions are followed correctly and the wires are tucked nicely, you would never know the system was in place until you opened the console or hit the gas pedal for break-neck acceleration.

This wiring harness will be tucked into the bottom of the C8 Corvette. The undertray of the C8 is flat and aerodynamic, and needs to be removed to install the ProMax wiring harness into the chassis tunnel.

The installation wasn’t the most challenging car project I have ever witnessed. Admittedly, I stood by while others did the work and I asked questions like, “Do you have any local lunch recommendations?” The C8 Corvette is a beast from the factory, but with some juice from Nitrous Outlet, safely controlled with the ProMax Controller, this thing is just a blue blur going down the track. So raise a glass to science and chemistry!

You are going to have to inform your significant other that their luggage will need to go between their legs because the frunk is now filled with two fat nitrous bottles from Nitrous Outlet to ensure parts of the road trip will be extremely quick.

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Rob Krider

Rob Krider will race absolutely anything. He is a multi-national champion racing driver and is also the author of the novel, Cadet Blues.
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