Stage 4 911/930 Carrera Turbo system (1984-1989) Boost your 3.3l 930 turbo or 911 3.2 Carrera with a Protomotive turbo system upgrade. What is a Stage 4 911/930 Carrera Turbo system? The Stage 4 turbo systems main signature is twin-turbo. Typically 100mm / 3.5 liter builds with twin-plug, we’ve also done 3.6 / 3.8’s as well. Running on pump fuel, the performance ranges from 620 to 680 crank hp. While with some meth injection of ms109, mid / high 700’s is possible. A 3.5L twin-plug / twin-turbo / gt2-evo cammed build with Protomotive’s Pressure sensing Motronics software is an amazing build with super response and power to compliment anything from a sleeper to a wild wide-body conversion. Producing approx. 680hp crank on pump fuel, using all of the oem electronics, these systems can even be maintained at the dealer with oem diagnostics tools. Does it require professional installation? The turbosystem can be installed by shops and DIY alike.  Although the internal build required should be carried out by a respected shop. Protomotive has Machining available in house for case boring, niro-rings and twin-plug. Additional information: Each system(results from testing at Protomotive and other various sources. Results not guaranteed due to condition of original engine) Available as Parts only as shown in this sale, or In-house installations available at additional cost. Protomotive Porsche Engine Building