1974 Porsche 911 RSR IROC for sale at The Ocatne Collection for GBP 99,995
1974 Porsche 911 RSR IROC
For the 1974 IROC Championship (which started in Dec. 1973), 1973 Carrera RSR models were fitted with the 3.0 engine and a flat “whale tail” in place of the ducktail spoiler. International Race of Champions (IROC) was a North American auto racing competition, promoted as an equivalent of an American All-Star Game or The Masters. Despite its name, the IROC was primarily associated with North American oval-racing culture.
Drivers raced identically-prepared stock cars set up by a single team of mechanics in an effort to make the race purely a test of driver ability. It was run with a small field of invited drivers (6–12). It was created and developed in 1972 by David Lockton, the developer of the Ontario Motor Speedway. Launched in 1973, Mark Donohue was the first driver to win the championship in 1974 in a Porsche Carrera RSR.
In 1974, Porsche created the Carrera RS 3.0 with mechanical fuel injection, its price was almost twice that of the 2.7 RS but it offered racing capability. The chassis was largely similar to that of the 1973 Carrera RSR and the brake system was from the Porsche 917. The use of thinner metal plate panels and a spartan interior enabled its weight to be reduced to around 900 kg.
The Carrera RSR 3.0 was sold to racing teams and scored wins in several major sports car races of the mid-1970s.
Porsche Motorsport LSD, G50/31 Gearbox, Smart Racing coilovers with remote Fox dampers, Recaro Pole Position seats, Lowered seat rails, Harnesses, Alcantara trim, Momo steering wheel with GT3 RS quick release, 3-point seat belts for the rear seats (cage removed), Lightweight GT3 RS side and rear glass, Single wiper arm, Track datalogging // video equipment including G-Monitors, MOTEC M600 ECU, Alpine head unit with Ipod connectivity, ATL fuel cell, Mocal oil cooler. Battery isolator, Fire extinguisher + cabin pull, Front cross brace.
This fantastic IROC tribute looks resplendent in Mexico blue – one of the signature colours from the Porsche palette that duplicates the car campaigned by Hulme, McCluskey and Pearson in the ’74 series. Starting life in the US, the bodyshell and chassis build was carried out by the respected Zuffenhaus organisation in Charlotte, North Carolina. Starting with a clean LHD 1974 911 shell, the team first carried out a myriad of chassis modifications to carry aftermarket 935 front and rear suspension leading to this sensational bodywork arrangement symbolic of the RSR IROC era.
The paintwork presents beautifully in a uniform and consistent hue all around the car, not often the case with track optimised examples with only some light peppering to the front air dam of real note.
Focused is the word to describe upon climbing aboard this track special, nestling down into a low slung Recaro bucket seat with the familar 5 dial arrangement in front. Fitted with a custom four-point interior roll cage accompanied with harnesses, the widened and modified bodyshell was stripped back bare before powder-coating the interior, engine bay and under bonnet areas for maximum durability and protection. The 993 RS gearbox may appear slightly out of place in the cabin although any concerns are soon quashed as it is a joy to operate – positive, slick and intuitive; it is matched to the 3.9 engine perfectly.
As well as an Alpine head unit with USB compatibility there is a host of track inspired tech available with data logging, G meter and in car camera.
ENGINE & TRANSMISSION
As with the rest of this incredible 911, the 3.8-litre flat six engine was specified with no regard to cost. Based around 964 engine cases and built by NineMeister (9M) in Warrington the dyno showed peak power of 405 bhp at 7800 rpm with a stunning 452Nm of torque at 5140 rpm.
While this was going on, a new Porsche 993RS G50/31 transmission was sourced from Porsche Germany, complete with steel synchros, Porsche Motorsport 40/65 differential and RS short shift kit. The 1974 rear section was replaced with the rear section of a 964 to take the upgraded transmission: this was a huge project complete with a subsequent change to relocate a 964 oil tank system and accommodate a 993 exhaust with side mufflers.
WHEELS, TYRES & BRAKES
An adjustable Smart Racing dual master cylinder controls the big 993 C4S front calipers, with 917 derived Porsche 930 calipers at the rear. The rear also features RSR reproduction handbrake calipers.
Wheels are 17” Zuffenhaus Fuchs, as used on Singer Design Porsche 911s, with Toyo R888′s on each corner.