Story and photos by Zach Mayne
When it comes to classic mid-engine Ferraris, one of the best looking by a wide margin is the original 12-cylinder Boxer. Judging a car’s aesthetics may be a largely subjective undertaking but you’d be hard pressed to find anyone who doesn’t find the 365BB and later 512BB stunning looking pieces of automotive art. Pininfarina did a masterful job of combining equal elements of elegance and aggression when they penned the Boxer’s rakish design. The lines of the sharp, flat nose sweep towards the back of the car, where it ends abruptly in a purposeful looking kamm-tail rear end. The side profile of the Boxer is equally exotic thanks to a rear quarter window shape that cuts a dramatic arc through the sheet metal, as well as a short rear overhang and long front overhang. Ferrari’s first mid engine supercar was far more aggressive looking than the 365 GTB Daytona coupe it replaced as well as prettier than it’s replacement, the Testarossa.
The Boxer’s looks were backed up by a powerful flat-12 motor, making this Ferrari one of the ultimate Gran Turismos of its era. The fact that it was never officially offered for sale in the U.S. made the Boxer all the more desirable. When Carobu Engineering took a restomod approach to building one, well, the results were justifiably outrageous. Originally built at the request of a California customer, this 512 looks near stock on the outside with the exception of larger, 3-piece wheels and a lower ride height. Underneath that blood red body however is a more powerful flat-12 engine and upgraded driveline that imbue this exotic with added speed and better handling, both of which are always a good thing in our book.
Though initially the customer approached Carobu to have an engine-out service done on the Ferrari, the work soon snowballed into a full-on project that would entail not only restoring the somewhat tatty Boxer but imbuing it with far more performance than it originally had. “A big focus of this project was extracting more power from the 5.0-liter, 12-cylinder Boxer engine so that it wouldn’t be embarrassed by more modern sports cars while maintaining a stock look.,” says Carobu’s co-owner, Tate Casey. “The plan included rebuilding the engine with a balanced combination of parts and modifications to produce a strong yet flexible power curve.”
Once the motor was dropped out of the car, Bert Wehr (the other co-owner of Carobu and the engine building side of the company) rebuilt it. The stock 82-mm bore and 78-mm stroke were retained but the piston liners were overbored to allow room for the new forged, 10.2:1 Razzo Rosso high compression pistons that replaced the originals. A balanced crankshaft was then mated to the stock connecting rods.
Using a Superflow flow bench and software that analyzes cylinder head airflow, attention was next focused on the flat-12’s heads. The intake ports were enlarged for more flow that in turn feed into port-matched intake manifolds. The stock exhaust valves were replaced with more durable Zanzi one-piece valves, which are stronger than the factory valves, the latter of which consist of a welded together head and stem that can snap suddenly. Carobu’s “Daytona” camshafts- with 247-degrees of duration- were chosen for more power at higher RPMs. Fuel delivery is handled by the ori ginal Weber carbs, which were rebuilt and tuned for the new motor.
On the exhaust end of the equation are stock exhaust headers that were ceramic coated for better heat dissipation and a stainless steel Tubi muffler. The latter not only sounds far better but weighs 40-lbs less than the stock muffler. To keep the more powerful motor cool, a custom aluminum radiator from Ron Davis was installed. On the dyno, the reborn 12-cylinder pumped out a healthy 364 crank horsepower at 6,500-rpm and 357 lb-ft of torque at 4,000-rpm. For a point of reference, that’s close to the power of a 512 BB/LM, a competition only beast that was based on the Boxer. Says Casey: “This is a 100-plus horsepower gain over the standard engine. We achieved our goals and verified all of the engine simulation and design work.”
To keep the performance of the Ferrari balanced, Carobu next began improving the chassis. The stock and original Konis shocks were worn out, with one even frozen, so these were sent out and rebuilt. In the process they were converted to height and stiffness adjustable coilovers with threaded bodies. Eibach racing springs replaced the original springs. On the stopping end of things are cross-drilled rotors and performance brake pads. The brakes are hidden by larger 17x8 and 17x10-inch Razzo Rosso 3-piece wheels wearing 235/50-17 front and 255/45 rear Pirelli P Zero tires.
During it's stay at Carobu the 512 was also restored cosmetically. The body was disassembled before being repainted in a custom and slightly brighter mix of the traditional Ferrari Rosso Corso, or "racing red". The interior was also completely redone into black and red leather, a marked improvement over the original black and white interior that the Ferrari left the factory with. There are also drilled pedals and a smaller, sportier MOMO steering wheel that brighten up the interior nicely. All in all, this Boxer is about as stunning as it gets when it comes to non-original, vintage Ferraris. And while the purists out there may be aghast, there's no denying that the results in this case were a complete home run.
Carobu Engineering • www.carobu.com • (949) 378-3226