- 6 Min Read
- By: Antonio Alvendia
Bisimoto Boxster 986 Twin Turbo: Could This Be The Ultimate Porsche Boxster?
Everything is about balance. Whether you’re discussing the laws of physics or building a racecar, balance is fundamental. It’s no wonder these principles are applied to open-wheel racecars. After all, when was the last time you saw a Formula 1 car with side-by-side seating? Never. Putting the driver in a central location is ideal for vehicle balance, which in turn lends to optimal handling.
From the Creative Cranium of Bisi
Custom car builders and fabricators have become far more common in today’s car culture, which is a fantastic indicator that the love of automobiles hasn’t completely died with the age of the hybrid and electric car. Even so, there are textbook builders, and then there are custom car builders. If you’ve paid any attention to the SEMA Show in the last two decades, you’ve probably seen some of the one-off creations presented by Bisi Ezerioha of Bisimoto Engineering. From one-thousand-horsepower Honda Civics and Odysseys to high-output Hyundai Sonatas and Santa Fes, Bisi engages build challenges with an open mind and a wealth of knowledge and creativity. When the popularity of the air-cooled Porsches began to gain traction among enthusiasts, Bisi had already started to expand his horizons to include this European marque. Bisi poured his thoughts and creativity into his 2018 SEMA Show project, this 2000 Porsche Boxster 986.
Building a Big, Bad, Balanced Boxster
Choosing to build the Boxster was not a difficult decision since Bisi had already turbocharged a 987 Cayman for his wife, Hedi. But her Cayman is a streetcar, heavy and laden with amenities. For all out performance, weight reduction was a must. What could be lighter than a roofless Cayman? The first generation Boxster has come down significantly in price due to age and its undesirable M96 engine with the failure-prone IMS bearing. Even so, Bisi loves fixing flaws, still making it an ideal build platform. It already had a 47/53 weight distribution thanks to its mid-engine configuration. Bisi decided to take this 986 to the next level, optimizing its handling traits by way of symmetry and balance, while fortifying the original 2.7-liter M96 engine not only to function reliably but also deliver more than twice the factory horsepower.
By now, you’ve noticed that the driver sits in the middle of the cockpit. This driving position ensures ideal weight distribution over the tires regardless of who hops into the seat. The Boxster shell was gutted of every extraneous ounce before RothFab came through and welded in a competition cage. Since the factory dash was scrapped in preparation for the center driving position, an additional reinforcement brace joined the front down bars to minimize flex while also serving as a mounting point for the steering shaft and the fluid reservoirs for the Wilwood pedal system. This cage features fixed door bracing strengthened with dimple die plates, along with numerous integrated braces joining the rear kickers, the main hoop and the shock towers. This meticulous effort not only provides rollover protection for the driver, but it lends to chassis stiffness for improved handling and feedback.
The tunnel that housed part of the driveline forward of the rear wheels was made flat to accommodate the fixed seat bracket that positions the Momo Safari-Daytona XL seat behind the center-mounted steering column.
The RothFab adjustable foot plate positions the Wilwood pedal box in the most comfortable position for drivers of just about any height. The master reservoirs for each pedal mount to the cross brace between the front down bars.
Since the Porsche employs a cable shifter linkage, repositioning the shifter mechanism to a comfortable position to the right of the center-mounted seat was a straightforward installation. A custom bracket positions the mechanism while a sheet metal plate positions the battery kill switch and ancillary switches within easy reach of the driver. The stick is topped with a SoCal Garage carbon-fiber shift knob.
A Momo steering wheel mounted to the end of the steering shaft, provides direct input to the steering rack. Bisi repurposed the horn buttons with a line lock on the right side, since he is, of course, a diehard drag racer. This line lock permits the holding of the front brakes while the rear brakes are disengaged, making victory burnouts or warming up the tires an easy process.
The left horn button is labeled “To Pass,” indicating that it is intended as a scramble boost button that delivers a momentary boost of just over one hundred additional horsepower.
Atop the column sits an AEM Electronics CD-7 digital dash that can display a variety of information from engine vitals to lap times. This dash ties in directly with the AEM Infinity engine management system for data contents.
One cool thing about the AEM CD-7 is the fact that you can custom program just about everything related to the display. When Bisi presses the "Push to Pass" button on the left side of his Momo steering wheel, he programmed the AEM unit to display a custom message saying "Danger to Manifold," a joking reference to the Fast&Furious movies.
A Racepak Vantage data system provides real-time and recorded monitoring of track position, telemetry, and datalogs to the crew.
Behind the rollbar's main hoop sits the M96 engine. It's all covered up by a black plastic cover (which was removed for this photo), and you need to take off the custom made Boxster carbon fiber roof in order to get to it.
Always Embracing the Underdog
Bisi is no stranger to taking the road less traveled. Rather than follow the masses when everyone was swapping in a Honda B-Series engine, Bisi championed the underwhelming and unpopular D-Series engine for what would become a 9-second, naturally-aspirated Insight drag car. Similarly, Bisi embraced the often vilified M96 engine that equipped the early water-cooled Porsches. This engine family suffered from notorious bearing failures that earned it a bad name in the Porsche community. Rather than turn from this engine, Bisi sought to fix the problem and make it the reliable and powerful engine Porsche engineers had originally envisioned it to be.
Bulletproofing the Boxer
Bisi broke down the 2.7-liter M96 engine and began the fortification process. The block halves were fitted with Golden Eagle ductile iron sleeves in preparation for the greater cylinder pressures of forced induction. Once honed, a six-pack of Traum forged aluminum pistons filled the cylinders. Bisimoto custom connecting rods join the pistons to the factory crankshaft.
All of the engine components were WPC treated prior to assembly. WPC treatment, Japanese nanotechnology, essentially shot peens the components to relieve stress while also creating a surface texture intended to trap engine oil and ensure proper lubrication.
Optimizing Heat Exchange
Turbocharging a mid-engine car comes with its own challenges when it comes to intercooling. Vents can only bring in so much ambient air to the back for cooling, and front mounting an intercooler becomes complex and heavy. The most efficient solution? Install an air-to-water intercooler instead. A Spearco air-to-water intercooler mounted in the trunk directly above the Precision Turbo 57mm turbochargers cools the aircharge before it flows through custom piping to the intake manifold of the M96 engine. A heat exchange core ensures that the water temperature stays cooled and steady.
Brains for Brawn
To orchestrate and monitor the fuel delivery and ignition timing as well as the myriad of sensors, Bisi chose AEM Electronics’ Infinity engine management system. This engine management system features hardware to rival high-end motorsports computers while offering accessibility and flexibility for consumers too. Relying on an ethanol content sensor, the Infinity EMS can seamlessly adjust the fuel and ignition tables to accommodate 100-percent gasoline, straight E85 or any mixture in between. Once calibrated, the M96 generated 420 horsepower to the wheels, with an additional 106 horsepower in reserve, ready at the push of the “To Pass” button on the steering wheel.
Next to the Spearco intercooler sits an AEM boost solenoid. Bisi has been working with AEM for years, and widely uses their products for all his builds.
Twins at the Back
Rear mounting the turbochargers has become a Bisimoto Engineering trademark that started with Bisi’s first Porsche build. The Precision Turbos are strategically placed along the long axis of the chassis, maintaining the theme of symmetry and balance.
AEM Induction Dryflow filters with Dry Flow Filter Wraps ensure that the Precision Turbos don’t ingest anything but clean ambient air.
Ballast for Balance
The fuel cell now takes its place under the hood, shifting some of the weight over the front tires. In doing so, Bisi achieves a nearly perfect 49/51 weight distribution.
From Convertible to Coupe
The Boxster’s skin is a complement of form and function. A 997 GT3 front end conversion gives the Boxster a modern facelift, but it lacked a proper roof. Bisi used a 987 Cayman roof to serve as the model for a custom PP carbon-fiber roof that mates up perfectly to the Boxster, providing a smooth transition from the top of the windshield to the trunk lid. Extreme Dimensions bumpers and side skirts further complement the body lines.
Bisi designed over fenders to house the wide and aggressive Carbon Revolution carbon fiber wheels fitted with Toyo R888R rubber.
Through the carbon fiber wheel spokes, you’ll catch a glimpse of the TAROX 8-piston brake calipers.
Equalizing Downforce for Handling
The chassis is dropped on KW Suspension V3 coilovers to lower the center of gravity. To keep the drive wheels pressed firmly to the pavement, a massive APR carbon-fiber wing mounts to the chassis by way of Bisimoto custom wing stays to deliver increased downforce. However, too much downforce at the back could cause the front end to get light, resulting in understeer. To maintain equal pressure over all four wheels, an APR splitter mounted to the front bumper complements the wing.
Bisi set out to build a powerful, lightweight track monster from a Boxster, and it appears he has succeeded. Producing up to 526 horsepower, the twin-turbocharged M96 generates more than twice its factory output. The center seat position, structural reinforcement, and strategically ballasted components lend to near perfect weight distribution to ensure optimal handling.
All things considered, the Boxster tips the Bisimoto scales at 2,550 pounds, a 200-plus pound weight reduction from stock, despite the additional structural reinforcement and twin turbo system. This could arguably be the ultimate balanced Boxster.
Story by Richard Fong
Photos by Antonio Alvendia
Antonio Alvendia is an aficionado of cameras, rare wheels, hip hop, and obscure aftermarket car accessories. He bought his first E39 Touring after seeing M5 Estates on photo trips to Europe, and now has sights set on restoring a classic Mercedes. Antonio was a principal photographer on the limited edition hardcover book on Singer Vehicle Design's Porsche 911 builds, entitled One More Than Ten. Future goals include returning to the Nurburgring to shoot the N24 race and driving the Nordschleife again. ••• Instagram : @MOTORMAVENS