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This Is How Bentley Tests the Ultra-Exclusive Bacalar’s Enhanced W12 Engine

The British carmaker has recently revealed that the first W12 engine intended for the exclusive Bacalar roofless grand tourer has completed the company’s three-stage testing process.
Bentley Bacalar 19 photos
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The Bacalar is set to be the company’s rarest, most exclusive modern-day vehicle. It will be built in just twelve units marking the return to coachbuilding by Bentley Mulliner.

Under the hood, it hides a Bentley-enhanced version of VW Group’s 6.0-liter W12 TSI engine, a powerplant considered by many to be one of the most advanced 12-cylinders in the world.

Compared to the W12 first used in the 2003 Continental GT, this version is updated to produce 650 hp and 900 Nm (667 lb-ft) of torque. That’s a 27% increase in horsepower and a 38% increase in torque while reducing the unit's overall emissions by no less than 28%.

Bentley Bacalar W12
Engineers have managed this feat by optimizing the crankcase, improving the lubrication and cooling systems, using the latest twin-scroll turbocharging technology, and developing a more efficient injection system.

Each of the twelve units designed exclusively for the Bacalar is hand-built in about six and a half hours by a team of 45 craftspeople before undergoing a complex three-stage testing process.

The first test is undertaken immediately after assembly and focuses on potential leakage issues by individually pressurizing the fuel, oil, and cooling systems to values between 0.2-5.0 bar (2.9-72 psi) and then measuring how the pressure drops over time.

Bentley Bacalar W12 Testing
If the drop in pressure is faster than anticipated, a leak is signaled, and fluid is sprayed onto the exterior of the engine to pinpoint its exact location. The next stage of the testing cycle is called the Cold Test and Bentley engineers tell us that this is the most critical test of the three.

Here, the engine is loaded onto a testbed platform and connected to the engine loom and management systems, while a large electric motor is coupled to it via the crankshaft. During a 15-minute cycle, the testing software measures 600 individual properties and characteristics to fine-tune the unit to Bentley standards.

Bentley Bacalar W12 Testing

For this test, the W12 runs at only 120 rpm so that any inconsistencies can be identified using a sample rate that highlights even the briefest of anomalies that would otherwise be undetectable if the engine were running at normal speeds.

This analysis is also useful for validating the engine's precise timing by using positioning data from sensors on the crankshaft, crankcase, and camshafts along with cylinder compression values.

This Cold Test is performed to gather cylinder-specific data before the exhaust manifolds, turbochargers, or other auxiliary components are fitted.

Bentley Bacalar W12 Testing
Once this test is completed, the engine moves on to the third and final test, which is called a Hot Test. Here, the complete engine assembly with all the aforementioned parts installed is checked, simulating real-world usage in the vehicle.

Before this test commences, a UV dye is added to help identify any leaks, while the cooling and fuel systems are pressurized with air and nitrogen for a final check. The engine is then turned on, and a highly skilled technician listens for any issues and checks for leaks with a UV lamp.

The resulting engine is arguably the most refined W12 unit out there, worthy of powering the ultra-exclusive Bacalar.

 
 
 
 
 

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