To save even more weight, thinner gauge steel was used for the doors, the sill covers were left off and ultra thin Glaverbel safety glass was installed at the sides and rear of the car.

Dramatically flared steel fenders were necessary, partly to cover the new wheels but also to enable the RSR version to run massively widened rims (Group 4 regulations dictated the competition version could be up to two-inches wider than the homologated base car).

Instead of chrome, a modern satin black finish was used for the window frames, door handles, exterior mirror and windscreen wipers.

‘Porsche’, ‘Carrera’ and ‘RS’ decals colour matched to the wheel centres were normally adhered to the front lid / bumper, down each flank and on the engine cover respectively.

Interior

In a similar fashion to the M471 Sport-optioned 2.7 Carrera RS, the new three-litre 911 Renn Sport came with fabric Recaro bucket seats, thin felt carpet, rubber floor mats, basic door trim, manual window winders and a simple black headliner.

The rear seats, clock, glovebox door and even the passenger sun visor were deleted. No audio system was originally fitted.

Behind the new-for-1974 three-spoke steering wheel were dials for road and engine speed inboard of which were combination read outs for fuel / oil level and oil temperature / oil pressure. The vacant clock area was simply blanked off.