The FR-S/BRZ, like the original Miata, has been called a “momentum car” which is car critic speak for under-powered. The Toyobaru is pure handling brilliance; balanced, responsive, and willing, but all you hear is crickets when you drop the hammer. Forced induction kit-makers love the sound of that scenario and Edelbrock has stepped up and developed one of its potent E-Force Supercharger Systems for the car’s 2.0-liter FA20 engine.
The Edelbrock Legacy
There is no questioning Edelbrock’s 75 years in the hot rod business, but this kit carries a particularly heavy burden as it is the company’s return to the sport compact market. The company’s initial foray into the scene was around 2003 when it introduced the Performer X Turbocharging Systems.
The kits featured the proven Garrett T28 turbo, were California smog legal, and focused on the Honda badge. One of the gems from the kit was the Performer X large-plenum intake manifold. It was artwork. The highly detailed manifold was popular with turbocharged street cars and all-motor drag racers alike. The engineering in the kits was excellent, the timing wasn’t. By 2003 a long line of Honda turbo kit manufacturers had already been established.
It’s different this time around, Edelbrock is in the game much sooner. We have been following the development of this supercharger for months, publishing behind the scenes reports on prototype development and charting its specs. So, when the real-deal production kit came into the light we were eager to see every detail.
Drift-Office, an Auburn, Washington-based tuning shop and a leader in the FR-S/BRZ tuning community, shared our enthusiasm and were the second in line to get a production FA20 kit. They were keen indeed, after receiving the kit on a Friday afternoon wrenches were turning on Saturday morning. We decided to follow along and chronicle the installation and dyno testing of the kit.
E-Force Supercharger Specs
The E-Force Supercharger is based on an Eaton TVS 1320. The TVS in the name stands for Twin Vortices Series and refers to the design of the twin four-lobe rotors that make the magic happen. The lobes are twisted 160 degrees and interlock as they spin, drawing in and trapping incoming air, compressing it, and forcing it into the engine.
Edelbrock packages the rotating assembly in a housing of its own creation. The FA20 application features a unique inverted design with long runners that allow for maximum flow at high RPM while retaining great daily driving characteristics. The unit’s integrated bypass valve is also commuter friendly, allowing little to no decrease in fuel economy during normal driving.
“The design follows suit with our typical E-Force parameters,” says Edelbrock’s Eric Blakely. “We aim for a short air intake path with long runners for an efficient high-flow design. In the case of this platform, we didn’t have to worry about hood clearance, but we still wanted to design a system that looks good under the hood and performs to our standards. Since this was our first entry back into the import market, we relied heavily on input from our accounts when it came to the aesthetics of the head unit. We went through a few design revisions until we ended up with what we have now.”
The E-Force kit utilizes a large dual pass air-to-water intercooler and heat exchanger to chill the incoming air. The setup includes a big heat exchanger that mounts behind the front bumper beam, a dedicated water pump, filler neck, and hoses.
The design of the air intake system is impressive. It is setup to provide a short and direct path to the supercharger. This set-up flows twice the volume of the stock box, and creates a ram-air effect to speed the flow into the supercharger.
Ease of installation is one of this kit’s strong suits. It is a simple remove and replace operation as the supercharger and manifold are one piece.
Once you get the stock manifold off it is a matter of clearing space by rerouting hoses and wiring that went over, around, and snaked through the manifold so you can simply drop the supercharger assembly on top of the FA20.
Edelbrock includes well-labeled extension wiring harnesses and longer hoses to make opening up room around the manifold super easy. “As an installer,” says Drift-Office owner Bob W., “I appreciate the no finagling aspect of the E-Force kit. It’s not every day that a kit like this installs as advertised right out of the box. It’s refreshing to experience a domestic installation philosophy in an import product. The term bolt-on installation means different things to different people, and we’ve been on the wrong side of that equation a few times.”
A 37-page, 173-step installation guide may sound intimidating but it’s the thoroughness of the guide that makes DIY installation feasible in the real world. “It also helps when all the parts fit like a glove and no ‘custom modifications’ were needed,” quips Bob W. The install used many pre-existing mounting points, the only extra-curricular activity was opening up an existing hole to mount the intercooler water pump. The kit was installed by two technicians in about five hours with nary a hiccup along the way.
Tuning The Combination
The E-Force Supercharger can be ordered with or without a tuning strategy. The stock tuning strategy consist of an EcuTek ProECU Programming Kit with E-Force tune pre-installed. This allows the user to flash and go to the tune of up to 242 wheel horsepower and 186 lb-ft of torque, numbers Edelbrock worked hard to produce.
“The biggest challenges we had were in the tuning area,” says Blakely. “After we baselined the car, we realized that the power range had a dip in the 3,500 to 4,500 rpm range that was noticeably felt while driving the car. So, it was important for us to invest a lot of time on the dyno and driving the car to eliminate this dip and keep the power curve building all the way through. Our tuning team did a great job of delivering a smooth power curve that builds all the way. We also realized that this engine runs hot, so our engineering staff spent a fair amount of time designing a new air box that flows two times the amount the stock box does. We also utilize an integrated dual-pass air-to-water intercooler that is designed for a V8 application to help ensure that the incoming air charge is cooled to keep air temps down.”
“Ultimately, we are always looking to increase performance without sacrificing daily driving manners,” Blakely continued. “We know that a car like this may see the track, but at the same time it’s most likely a daily driver. So we always spend a lot of our time on the tune to make sure the car performs great in both areas. Plus, we also like to give a tuner plenty of potential to work with so they can pull more power out of the system for various racing applications.”
Drift-Office 92-Octane Tune
Drift-Office was going for extra credit by tuning the system with its own tuning strategy. This was a tricky tune because the customer was from Canada where the fuel quality is not the same as in the U.S. Canada has a Chevron 94 gas but it has the octane equivalent of around 90 octane as rated here. Also, Washington has 92 octane so there is more potential for power compared to the 91 octane gas in California. Since the car owner spends time on both sides of the border, Drift-Office created two tunes for the car using an EcuTek ProECU. The Canadian tune produced substantially less than the final U.S. tune. “It’s all about the detonation threshold,” says Bob W. “With inferior octane you can go into the ignition tables and take timing out until the engine does not show detonation but there is a compromise at work here. Pulling timing produces higher EGT temperatures, thereby producing more heat. More heat means more headaches.”
“Superior octane content means the timing can be optimized for power, not retarded to fend off knock or detonation. You will eventually face a timing crisis but the engine will be running more boost and make more power compared to the similar timing crisis in a Canadian-tuned car. The 10 psi of this kit seems to be the FA20’s sweet spot on pump gas. I would like to give E85 a whirl one of these days though.”
Before the install the Scion, which has a RevWorks UEL header and 2.5-inch Perrin exhaust, baselined at 167.6 horsepower on Drift-Office’s DynoJet. In the final stanza the FR-S spun the rollers to the tune of 286.3 horsepower, a whopping 118.6 jump in output. Torque also enjoyed a big bump, increasing from 138.6 lb-ft pre E-Force Supercharger to 213.9 lb-ft under pressure, a gain of 75.3 lb-ft.
Got a heavy right foot? Own a Scion FR-S or Subaru BRZ? Edelbrock will make you wish your right foot was even heavier. The E-Force Supercharger provides triple-digit peak power gains and substantial jumps throughout the rpm range, looks great under the hood, installs over a weekend, and is built to last for many miles on the street and/or many hot laps at the track. Our only question … when will a Stage 2 pulley be introduced?