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Singer Porsche 911 ACS is Rally Racing Reimagined

singer porche 911 rally racing

At Anthony’s Auto Craft, we come across some unique and cool vehicles but every now and then a car comes a long that causes us to pause in awe. Singer, a company specializing in restoration and design modification of existing air-cooled 911s, has done it in spades with its jaw dropping ACS (All-terrain Competition Study).

Inspired by the off-road racing Porsche Rally cars of the 80s and 90s, the ACS is a masterpiece in both form and function. It is quite a departure from the high-horsepower, air-cooled classics on which Singer has built a reputation.

Singer Porsche 911 ACS

Singer and Richard Tuthill

In partnership with Richard Tuthill of Tuthill Porsche, a team who has dominated Off-Road Events for decades, Singer set out to build the ultimate Rally 911, and we believe they’ve succeeded.

Don’t believe us? Have a look for yourself:

The Singer Tuthill experiment did not disappoint. This Off-Road race ready 911 features all wheel drive, a revised chassis, & racing spec twin turbochargers.

The results of this long awaited experiment have been nothing short of amazing.

Singer Porsche 911 ACS Specs:

Singer Porsche 911 ACS Rally

From Tuthill Porsche

Modifications developed for the Porsche 911 Reimagined by Singer All-terrain Competition Study include:

  • Off-road competition capability, conceived with events such as the Baja 1000 and Dakar Rally in mind, but suitable for a range of surfaces
  • Dramatically increased ride height, suspension travel and overall strength
  • Carbon fiber body panels suited to quick replacement and easy under-body access
  • Permanent AWD
  • A twin-turbocharged, 3.6L, air-cooled flat-six with power starting at 450hp
  • Sequential racing transmission with front, center and rear limited-slip differentials

Summary Technical Specifications

  • 1990 Type 964 Porsche 911
  • Core strengthening to monocoque for heavy duty off-road use, carbon fiber body panels and off-road race modifications including:

Suspension, wheels and brakes:

  • Specialized long-travel suspension with twin, 5-way adjustable dampers per corner (8 dampers total)
  • Forged aluminum 8×16” wheels with BF Goodrich All-Terrain tires
  • 4-piston, monobloc steel disc brakes with hydraulic handbrake


  • 3.6L twin turbo-charged, air-cooled, Porsche flat-six
  • Water-to-air inter-coolers, with individual-bank charge coolers housed within the plenum and cooled by clamshell-mounted radiator
  • Tuned for the demands of each event, power starts at 450hp and 420lb ft torque


  • 5-speed sequential dog-box enabling flat-shifting.
  • Manual and paddle-shift capable
  • Permanent AWD
  • Front, center and rear, mechanical, plated limited-slip differentials

Additional Specialized Equipment:

  • Long-range fuel tank
  • 2 x full-size spare race wheels and tires in front trunk area and rear storage area
  • Full FIA specification roll cage
  • Bespoke competition seats with FIA certification
  • Re-hydration system for driver and navigator
  • State-of-the-art GPS race navigation system

Singer Porsche 911 ACS Production

There are currently two ACS builds planned – both for the same client. The second car will be in Corsica Red configured for high speed, high grip tarmac events. As for future iterations and availability to the public, we will have to wait patiently for Singer to make that call.