Porsche recently unveiled its mid-cycle refreshed 2017 911 Carrera and Carrera S models. With the mid-cycle refresh, the 911 gets redesigned front and rear bumpers, slight equipment changes, and new twin-turbocharged 3.0 L flat-six engine.
For many 911 purists, the death of the naturally aspirated engine can be a bit hard to swallow at first. But, I am sure that when they see and feel the increase in performance and fuel efficiency, they will soon get over the loss of the naturally aspirated engines.
In the base 911 Carrera, the new 3.0 L twin-turbo flat-six engine is good for 370 horsepower and 332 lb.ft. torque. The same engine in the 911 Carrera S produces 420 horsepower and 369 lb.ft. torque. So, even though the displacement is a bit lower than it was before, the new engine actually makes more power and torque. Another benefit of the new turbocharged engine is that the fuel efficiency ratings has gone up by 2-3 mpg across the range.
With that being said, here are the 10 Things You Need To Know About Porsche 911’s New Engine:
The Engine Is Mildly Boosted
The Porsche Carrera loses 0.4 liters and the Carrera S loses 0.8 liters of displacement than before. Compression ration in both models drop from 12.5:1 to 10.1:1. Peak boost is set at 13.1 pressure per square inch (psi) in the Carrera and 16.9 psi in the Carrera S.
It Is Still Rev Happy
The 3.0 L 9A2 twin-turbo flat-six engine only loses 300 rpms compared to the naturally aspirated engine. The motor redlines at 7400 rpm and max engine speed is 7500 rpm.
It Has Iron Sleeves
To counter higher cylinder pressure, coated on iron sleeves were necessary, and proved to be helpful. It was designed with microscopic sized spaces for oil pockets, which lower piston friction, which results in increased power and fuel efficiency.
Overall Weight Is Reduced
Adding two turbos and the necessary cooling and plumbing added 77 pounds to the powertrain, and with some creative engineering, Porsche took 33 pounds back out of the unit.
. An injection molded plastic oil pan replaces the old aluminum unit, which saved 4.4 pounds.
. The crankcase uses a new aluminum alloy and different design and saves 3.3 pounds.
. A newly designed oil pump saves an additional 3.6 pounds.
. Major weight is reduced by a newly designed exhaust system, which shaves a whopping 15.4 pounds.
. Thinner walled cooling passages and several other areas count for the rest of the weight savings.
Bring On The Wail
To keep the trademark 911 flat-six wail and immerse the owner in Porsche experience, the engineers added additional plumbing to channel induction noise into the cabin.
It Has Forced Air Intake
The updated 911 Carrera models feature a new vertically opening air inlets after the rear spoiler that feed both the intake and the air-to-air intercoolers.
Front And Center Fuel Injection
The spark plug and fuel injector rest in the middle top of the combustion chamber. The fuel injector runs at 3652 psi and squirts fuel into the chamber up to 3 times per cycle. The central location aids fuel and air mixing and completes the ignition cycle.
Water Pump Is Clutched
A clutched water pump allows complete decoupling from the engine, which helps the engine reach operating temps faster and saves fuel by only spinning the pump when necessary. The A/C compressor is also clutched to save fuel.
To reduce turbo lags, the mono-scroll fixed-vane turbochargers use a vacuum-operated wastegate system to manage charge pressure. Also, whether the driver is at full throttle or completely off the gas, air is flowing to the turbos to help them spool. Importantly, the compressors don’t need to build up a very high pressure to spool the turbos.
It Is A Torque Monster
Peak torque now arrives at 1500 rpms and holds till more than 5000 rpms. Peak power comes in at 6500 rpms. Porsche says between peak and 7500 rpm engine speed, power drops by less than 5%. S, the Carrera makes 352 horsepower at 7500 rpms and the Carrera S makes 399 horsepower at 7500 rpms.
Information and Image Source: PORSCHE USA