Built to demolish off-road stages, the Singer ACS is a 2021 interpretation of the legendary 911 rally cars that Porsche built in the 1980s. Watch as Tuthill Porsche shows what it can do.

What is the Singer ACS all about?

The Porsche 911 Reimagined by Singer All-terrain Competition Study (ACS) was undertaken by Singer, in partnership with Richard Tuthill. The idea actually came as a result of a request from a Singer client for a modified air-cooled Porsche 911 that could compete in off-road racing.

The client didn’t just request one, though, no, he requested two. The first of which is featured here in Parallax white, and focuses on high-speed desert rallying. The second is finished in Corsica Red and is built for high-speed, high-grip tarmac stages.

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 fibre body panels suited to quick replacement and easy underbody access
  • Permanent AWD
  • A twin-turbocharged, 3.6L, air-cooled flat-six with power starting at 450hp
  • Sequential racing transmission with front, centre and rear limited-slip differentials

Singer ACS: Tech Specs

  • 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:

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


  • 3.6L twin turbo-charged, air-cooled, Porsche flat-six
  • Water-to-air intercoolers, 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, centre and rear, mechanical, plated limited-slip differentials

Additional Specialised Equipment:

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