Stillen VQ37 Supercharger System - Import Tuner Magazine

After more than a year of development and testing, Stillen announces its CARB approval of their Nissan 370Z (Z34) G37 Supercharger system. The 50-state legal kit goes without notice as the company that has brought many “firsts” in our industry including the first CARB-legal forced-induction solution for the Z33 350Z is among one of many groundbreaking accomplishments Stillen has achieved within its 25 years of business. The Nissan/Infiniti VQ37 supercharger system helps add some serious gusto to your ride by increasing horsepower from 282 to over 416 whp (depending on vehicle and modifications) on 91-octane pump gas. Unlike Stillen’s supercharger kit for the old VQ35 engine that required a custom cowl-type hood for clearance, the new supercharger kit is compact enough that all the hardware squeezes within the confines of the engine bay and is designed to fit with a stock 370Z or G37 hood to give the car a factory appearance. Each kit comes with a quiet, self-lubricated Vortech V-3 centrifugal supercharger, custom cast-aluminum intake manifold, complete air-to-water intercooler system, as well as an ECU reflash, datalogger, and diagnostic scanner. The supercharger system is designed to work with both automatic and six-speed vehicles, including convertible and all-wheel-drive models. This kit is designed for specific owners who want big horsepower gains and are not worried about legality or warranties.

The illustration below shows horsepower robbing heat soak from a typical air-to-air intercooler kit. Compressed air is forced through the charge pipes, often passing over the engine, causing the once cool air to heat up by the time it reached the intake manifold.

The Stillen air-to-water intercooler maintains a more efficient setup as a cooler/denser air intake charge is achieved before entering the engine, which translates into a more efficient setup which creates more horsepower.

The VQ37DE, the most current evolution of Nissan’s VQ family of V-6 engines is factory rated at 332 hp and 270 lb-ft of torque in the Nissan 370Z and 330 hp and 270 lb-ft of torque for the Infiniti G37.

The kit comes complete with everything necessary to install, to the point you probably won’t have to leave your garage to complete the installation as any average DIY mechanic can install the kit in less than 20 hours.

Supercharged or turbocharged applications require a more fuel capacity than naturally aspirated applications. The Stillen supercharger kit comes complete with a set of larger-sized (six) 600cc/min fuel injectors to quench the vehicle’s fuel demands.

In order to combat heat soak from the supercharger and maintain a cooler combustion process, Stillen designed their own cast-aluminum intake manifold, which houses an air-to-water intercooler inside the unit. By designing the manifold with a built-in intercooler the supercharger kit cools the air charge immediately before the air enters the engine.

Stillen also improved upon the factory intake manifold’s design by designing their own manifold with an increased runner length and larger plenum size to increase torque and volumetric efficiency.

Stillen engineers claimed initial testing with the new setup showed temperature drops of over 100 degrees of heat after the intercooler immediately before the air enters the engine. The efficiency is a big reason why air-to-water intercoolers have been proven to be the most efficient intercoolers available.

Installation of the kit is straightforward and doesn’t require any specialized tools. Installing the right-side manifold bolts does require plenty of patience along with an extra set of eyes that will come in handy to properly secure the bolts.

Proper airflow was another major consideration when designing the supercharger system. Because the stock 370Z and G37 cars are prone to elevated oil temperatures, even after a few laps around a race course or hard driving on the street, Stillen designed their heat exchanger and air intake system to not interfere with their optional race oil cooler, automatic transmission cooler, and power steering cooler.

Also included with every supercharger kit is a high-flow 255-lph in-tank fuel pump replacement along with detailed instructions on how to properly wire-up the unit.

The intercooler system uses its own separate coolant path that does not get routed in with the engine coolant. An added benefit to the air-to-water intercooler design is that the heat exchanger (mounted in front of the radiator to cool the coolant) is very thin. Because water is four times more efficient at dissipating heat than air, Stillen was able to design a more compact heat exchanger to cool the water, thus preventing the front-mounted heat exchanger from blocking the airflow supplying cool air to other vital coolers such as the radiator, engine oil cooler, transmission cooler, power steering cooler, or the A/C condenser. The kit also includes all necessary installation components including a charge cooler water storage tank with hoses, water pump, clamps, and plumbing.

The air inlet was engineered using a Y-pipe–designed cast-aluminum intake tube that relocates the MAF sensors, retaining a “draw through” configuration. The MAF sensors are located in front of the forced-induction device to get an accurate reading of air volume. Stillen chose this route simply because this is what Nissan recommends, and over the years, have learned that the MAF sensor that Nissan uses is not designed to be “blown through”, or post forced induction. Two examples would be the Nissan GT-R and the 300ZX in which both cars use a draw-through MAF sensor setup.

Vortech V3 Supercharger

The Vortech V-3 series supercharger unit contains the same internal geardrive system as its big brothers and was designed to work safely with stock engines and all emissions equipment. The supercharger features an internally lubricated transmission and integrated gear case baffling for proper oil control. That means there’s no need for running additional lines from the oil pan or separate coolers.

Stillen Supercharger kit

• Vortech V-3 Centrifugal Supercharger Unit
• Stillen purpose designed cast-aluminum intake manifold with long runners for increased torque
• Complete system includes pre-assembled Vortech V-3 supercharger assembly, air intake with polished air charge pipe and genuine K&N intake filters, fuel injectors, high-flow fuel pump, air-to-water intercooler, UpRev ECU Tuning cable/software and detailed installation instructions.
• Optional three-year/36,000-mile powertrain warranty
• Made in the USA
• 50-state emissions legal (E.O. Number D-436-17)

Although the Vortech V-3 SCI model has physical dimensions equal to the S-Trim supercharger, the impeller speed potential efficiency on the V-3 SCI model is slightly improved over the S-Trim for increased mid to top end power and uses a V-belt design, which is regarded as a much quieter system.

A close-up image of the backside of the supercharger with its laser-cut billet aluminum mounting assembly.

Vortech V-3 SCI-Trim Supercharger

Performance SpecsDimensions Max Speed: 53,000 rpmDischarge OD: 2.75 inches Max Boost: 17 psiInlet OD: 3.5 inches Max Flow: 1,050 cfmDischarge ID: 2.38 inches Max Power: 725 hpInducer Diameter: 3.1 inches Peak Efficiency: 75 percent

To handle the fuel management for the supercharger system Stillen has gone directly to the ECU. By changing out to larger injectors and fuel pump (supplied in every complete kit) Stillen is able to take control of the factory ECU and re-map it for the boosted application. This tuning method is handled via reflash using the UpRev software tuned by Stillen engineers. This supercharger system comes in two options: fully tuned (most popular) or tuner. The tuner kit does not include fuel management or a warranty.

  |   Stillen VQ37 Supercharger System

Upon installation of the supercharger kit, we threw the 370Z into the dyno to document the vehicle’s increased power.

  |   Stillen VQ37 Supercharger System   |   Stillen VQ37 Supercharger System

The 370Z six-speed with a Stillen exhaust, supercharger kit, and CARB tuning on 91- octane pump gas at 8 psi made 134 hp and 80.5 lb-ft of torque over the stock baseline run. Horsepower numbers may vary depending on the condition of the engine and fuel octane, but Stillen has reported customers running similar setups with slightly more boost and tuning for 93 octane, hitting 450 whp all day long.

  |   Stillen VQ37 Supercharger System

Supercharging the G37 allowed Stillen to achieve a gain of 133 hp and 69 lb-ft of torque on 91-octane fuel and their high-flow exhaust. Stillen also offers an optional 9-pound pulley kit. The kit offers additional power, but will void any warranty from Stillen.

Driving Impressions

Lay into the throttle from a standstill and the newly forced-fed powerplant comes to life in an instant. Even with the VDC on, we couldn’t use more than a quarter throttle for launch without initiating wheelspin as the car wanted to automatically pitch sideways into a slow speed drift. Testing the vehicle at El Toro Air Station based in Irvine, CA, netted us a trap speed of 120 mph in the quarter-mile while the 370Z’s tires barked and pleaded for mercy with every high-speed turn. Knowing your 370Z/G37 is making 400-500 whp and is 50-state emissions legal next time you pull beside a police officer is simply icing on the cake.

  |   Stillen VQ37 Supercharger System