David S. Wallens
David S. Wallens Editorial Director
5/21/12 4:33 p.m.

The words "free horsepower" and "Porsche 911" rarely go together, but we found something for our 1984 Porsche 911 Carrera. Our car was originally sold in California, and the options sticker includes the code C03: California car. We gleaned some good info from a post on the Pelican Parts message board by chip tuner Steve Wong:

"If you look in the specifications of an 84-86 owner's manual, it will show that 49 state cars are rated at 207 hp, with a 0-60 at 6.1 seconds. A California car is rated at 200 hp with a 6.7 sec 0-60. The only difference is the connection of the pin 10 brown wires on the DME harness which retards the ignition timing for reduced NOx, and eliminates any fuel enrichment for lower HC and CO, effectively also killing throttle response. These wires are also connected for Japan spec cars. The DME chip remains unchanged. The emissions label under the engine decklid will also specify California emission approved. In the interest of performance, just disconnect those brown wires!

"The above only applies to catalyst spec cars, and not to ROW 3.2s without an O2. In the ROW 87-89 cars, those wires are used in conjunction with a ROZ adapter to select from one of three region coding maps within the DME programming."

The DME (also known as an ECU) is located beneath the driver's seat, and that brown jumper wire can be found at the front of the unit. Access is super-easy, and the entire process took us about a minute.

Afterward, the engine seems smoother and torquier, while the car definitely feels a tad quicker. Just hopeful wishing? We'll be sure to test this one with some real calibrated equipment.

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