New Cylinder Heads for Air-Cooled Porsche 911s Allow 12,000 RPM Revs

These innovative cylinder heads are the latest offering from Swindon Powertrain, the preferred supplier of engines for the British Touring Car Championship, which has also been involved in the Jaguar C-X75 supercar project. Specifically designed to fit the Porsche M64 engine series, which powered the last two models of air-cooled 911s, the 964 and 993. These heads come with four valves per cylinder, a vast improvement from the original single-overhead-cam three-valve setup commonly found in minivans of that era. Although they retain the single-cam design, these heads are a significant upgrade from the standard configuration.

These heads now boast four valves per cylinder, improving airflow. They also increase compression from around 11:1, as per 964UK.com, to 11.5:1, with the option for 12:1 if you opt for the right pistons. Additionally, they are approximately 7.7 pounds lighter than the original heads, potentially enhancing the vehicle’s handling.

Moreover, they seamlessly integrate with the stock engine’s cam drive, oiling system, valve covers, crankcases, and exhaust components. They are accompanied by an installation guide and have been designed to accommodate a 997 GT3 intake and 718 ignition coils for those pursuing a restoration-modification project. For enthusiasts embarking on this path, Swindon Powertrain offers compatibility with power steering drive systems, CNC porting, a carbon fiber fan shroud, and a selection of cam profiles to suit individual preferences.

It’s often speculated that boosting power in Porsche’s air-cooled engines can be a costly endeavor, and this instance seems to confirm that notion. The pricing for these cutting-edge heads is not publicly listed on Swindon Powertrain’s website, and as the saying goes, if you have to inquire about the price, it may be out of your budget. Nevertheless, given the current market values of air-cooled 911s, the cost is likely inconsequential to their owners—especially those striving to maximize every bit of horsepower.

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