A Porsche 911 hybrid is expected in the Fall of 2022, when it will be offered publicly from Porsche AG using the 991.2 official model number. Unlike existing Porsche hybrids like the Panamera and Cayenne, the 911’s hybrid system, like the 918 Spyder, will likely be focused on adding performance instead of efficiency. Although the Porsche 911 hybrid isn’t available from Porsche AG yet, Vonnen’s Shadow Drive system can be added as a retrofit to hybridize™ the Porsche 911 (as well as select Boxsters and Caymans) from 1965 on with 150 extra horsepower and an additional 150 lb/ft of torque.

Absolutely, hybrids can be optimized for performance too. Many hyper-cars and supercars, including the Porsche 918 Spyder, La Ferrari, and Mclaren P1 are using hybrid systems to boost performance, especially by taking advantage of the electric motors’ ability to deliver power at very low rpm. This allows the engine and electric motor to work together to maximize power delivery across a wide power band. Vonnen’s Shadow Drive hybrid technology can be adapted to fit virtually any make or model vehicle and add 150 additional horsepower on top of what the engine is already producing.

Due to their high-voltage electrical systems, retrofitting a hybrid system into an existing vehicle should only be done by specially trained and certified technicians. A hybrid system is not generally mechanically complex, but battery chemistries and wiring do require special care and training.

It is possible to retrofit a hybrid system on most cars and trucks. Vonnen’s Shadow Drive system incorporates a thin profile electric motor between the transmission and engine, providing substantial electric power on top of what the engine already produces. Nearly all cars and trucks have enough space in the transmission bell housing to accommodate this hybrid installation approach and it works on a wide variety of vehicles regardless of which wheels are driven or whether they use manual or automatic transmissions.

Shadow Drive is configurable with up to 150 hp and 150 lb-ft of assistance. This is managed through a proprietary smartphone app.

Shadow Drive begins making power at idle continuing through redline. It is the most significant way to add power in the desirable “area under the curve” of a car’s performance envelope. In terms of feel, it’s seamless with no clear on/off boost sensation. Power is abundant throughout and mirrors exactly how your car felt before, but amplified.

Yes, Shadow Drive layers with traditional mechanical performance modifications regardless of engine power output. It provides power assistance inverse to the engine’s power curve so that boost is most significant where the internal combustion engine has lower torque. In practical terms, what this means is that it torque fills on engines with big, laggy turbos or aggressive cam profiles. It augments power as the turbos spool or the engine comes on cam.

Power is available in bursts via normal application of the throttle. Boost is mapped to throttle position to deliver more electric assistance at higher throttle positions. The battery is replenished during normal driving through regenerative brake recharge. Drive modes are user selectable via the smartphone app.

Shadow Drive does not require plugging in. It is self-regenerative via the braking system and is also capable of recharging with opportunistic harvesting of surplus power from the crankshaft.

The battery has 1kWh of energy storage. It has a peak output of 110kW (150 hp) and is liquid cooled.

Shadow Drive adds about 170 pounds, but does not compromise the classic rear-biased character of the car. It is a fully integrated system comprised of the battery, motor, inverter control unit, radiators (for battery and hybrid motor cooling) and piping. As a comparison, the entire system adds a similar amount of weight as a full tank of fuel.

Shadow Drive is $75,000 installed

Approximately one week

Shadow Drive is designed to be self-contained. Installation is completed without chassis modifications, and has been designed to be integrated within the stock 911 vehicle with minimal additional components. It is a very transparent application.

All configurations.

There is no need to modify brakes when using the Shadow Drive hybrid system.

Shadow Drive adds two small radiators in front of the stock units in the front of the vehicle. There are two different coolant loops – one for the battery and one for the electric motor. This optimizes the entire system for thermal efficiency, keeping the battery at near ambient temperature and the electric motor running at temperatures lower than engine cooling temperature – in other words optimal performance windows for all three components in the system.

We have designed against this so that the battery will not discharge to the point that it will compromise the ability to start the engine. The battery management software was designed with this in mind. In the event the battery fully depletes during storage, it can be plugged into a wall outlet to recharge. The stock battery remains and still powers all auxiliary systems such as alarm, locking, etc.

Yes, Shadow Drive is reversible and can be removed for installation into another car, or for any other reason to return the vehicle to stock form.

Vehicle emissions remain unaltered.

Fuel consumption may change by small amounts when the system is not providing power due to added weight. However from what we have seen in use, it actually saves fuel as drivers gain more low-end power assistance and tend to put less load on the combustion engine.

Vonnen offers a 1-year limited warranty on parts and labor, optionally extendable.

Vonnen has a network of authorized service partners available to service Shadow Drive.

We don’t expect to see significant performance degradation with the batteries in a span of at least ten years as they have been optimized for fast-cycle use.

Battery prices continue to come down as energy density and storage technologies advance. We can’t say an exact price at this time given that, but they will definitely become more affordable.

On the west coast Vonnen can install a hybrid system or in the mid-west Kelly Moss Racing is a certified hybrid installer.

Because Shadow Drive is a complete hybrid overlay, it will not affect the performance of the vehicle drivetrain in any way when not in use.

The engine’s computer sees Shadow Drive as the equivalent of driving with a very strong tailwind. In other words, it just perceives that it is working less hard to meet its factory calibrated performance level. It neither sees nor interacts with Shadow Drive.