A Deep Dive Comparison of the 9A1 and 9A2 Engines

As you’ve surely heard by now, Porsche is going full turbo for its 911 lineup. Gone is the 9A1 engine from the 981 and 991, and here is the 9A2 forced induction engine. Naturally, the comparisons have already begun. With the available information and a few photos of the engines, Rennlist user Petevb decided to do a technical breakdown of what’s different and what remains the same.

Here are a couple key notes from his analysis:

• “Visually it appears to share most components and castings, with the turbo plumbing bolted on after the fact, adding 77 total pounds. Lighter engine components, particularly the exhaust, offset some of this weight, bringing total weight gain to 44 lbs.”
• “2.981 liter displacement suggests Porsche has no intention of racing this engine: engines that race have round numbers to maximize displacement (3.800 liters for the old Carrera S, 3.600 for the 76.4 mm x 100 mm Mezgers, etc).”
• “Power and torque are both up 20 hp and 44 ft/lbs, respectively, weight is up even more.”
• “The 991.2 is faster than the 991.1, but technically the engines seem to have moved the game backwards in many ways- more complexity, more weight, little upside other efficiency.”

Check out the full comparison HERE.

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Via [Petevb]