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The Pinnacle of Porsche

For those who prefer the 1970's, the pinnacle of Porsche came in 1973. That's when the Carrera RS was introduced. Many argue that later models were more GT than pure sports car. Others who've never driven an early model may scoff at this outlook. "How could any 911 be considered a GT?" It's a reasonable question, but next to the Carrera RS, very few street cars can be considered pure sports cars.

Before looking at the RS, lets look at the model it was based on - the 1972/73 911.

In 1972, 911 engine size was increased from 2.2 liters to 2.4. This was accomplished with a forged crankshaft whose stroke was increased to 70.4 millimeters. The result was more torque, making the car a lot more driveable. Although they were the same bore, 2.4 pistons were not the same as those used in the 2.2 liter. Part of the reason for the piston change was to meet the new unleaded fuel requirement. On U.S. spec cars, the new pistons had lower compression ratios. However, all three U.S. spec models, the T, E, and S, received mechanical fuel injection. This resulted in the T having 10 HP more than it's European counterpart.

The 1973.5 911T was the first 911 to use Bosch K-Jetronic (CIS) fuel injection. HP levels stayed at 140, but drivability and maintenance requirements were greatly improved. Specifically, fuel economy was increased, smog levels decreased, and there was no longer a requirement to set the MFI timing, synchronize the air stacks, or adjust the main and idle control mixtures. There was a downside though. 911's with properly adjusted MFI appear to be a lot more powerful.

Besides the engine, a number of other changes were introduced in 1972. The dry sump oil tank was moved from behind the right rear wheel, to just in front of it. There was also an oil filler door added to the right rear fender. This was done in an effort to improve handling. By moving the weight of the tank and it's nine quarts of oil further up the wheel base, the hope was the 911's propensity for oversteer would be reduced. That idea didn't work out so well. Some say it was because people inadvertently opened the "new for 1972" fender mounted oil filler door, and added gasoline. In 1973, a stainless steel tank was moved back to the original position and the fender filler was eliminated.

1972 also saw the introduction of the 915 transmission. The 915 replaced the 901 and it's dogleg first gear. On a 901, first gear was to the far left and down. Second through fifth were up and to the right in a more standard H pattern. Standard if you never used 1st. The 915 transmission had stronger gears, improved synchros, upgraded bearings, increased spacing between the input and output shafts, and a redesigned clutch release bearing.

Other than the oil tank, the 1972 and 73 cars had very few differences. In 1973, the outside mirrors were rectangular, and black trim was used around the front turn signals and rear taillights.

In 1973, the Carrera RS 2.7 made it's debut. The engine size was increased by increasing the bore from 84 millimeters to 90 millimeters. These cars had 8.5:1 compression and mechanical fuel injection. Basically, they were 2.4 S engines with larger pistons and cylinders. These engines produced 210 HP and 188 lb-ft of torque. In 1973, Autocar magazine reported the Carrera RS did a 5.5 second zero to sixty sprint, a 14.1 second quarter mile pass, and had a 149 MPH top speed. The M471 option code was a Carrera RS Sport. These were lightweight models with body panels made of thin gauge steel and thinner glass. Insulation, carpeting, rear seats, and interior trim were all deleted. These cars weighed 2116 pounds. They came with Recaro sport seats, a ducktail rear spoiler, and larger wheels and tires (195/60 15's on 6 x15's up front and 215/60 15's on 7 x 15 out back). Only 200 of these were built, and they had a list price of $10,200. The M472 option code was a Carrera RS Touring. Unlike the M471 whose audience was the club sport market, these were more luxurious versions of the RS. The M472 was equipped similarly to that of a 911S. The M472 weighed 33 pounds more than than the M471. 1308 Touring models were built with a list price of $11,000

Prices supplied by the N.A.D.A. guide

© 2005 Marcus Blair Fitzhugh

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