HISTORY & TECH
The same model with three states of tune wasn’t new at Porsche. Excluding the twin-cam Carrera, the 356 B was available with 60, 75 or 90PS, the run-out 356C of 1963-65 came with either 75 or 95PS, while the new 911 was the flagship model with 130PS.
Besides expanding the appeal of the 911 with a cheaper version, the T also brought cost savings to a Porsche that was always concerned with expenditure. The thermal stresses on this lowest-powered flat six meant that the expensive Biral cylinders could be replaced by cast iron, while lower rotating speeds meant that a cheaper crankshaft without counterweights could be fitted without compromising the bearings.
This also brought a weight saving of 6kg. Cast-iron rockers replaced the steel items fitted to the E and S engines, but the T engine retained the triple-throat Weber carburettors of its sisters. Porsche had selected the T as its homologation model because it was the lightest of the trio. It would provide the basis for the S/T racers (and famously for the Carrera 2.7 RS). Reducing the T’s power output was achieved by lowering the compression ratio to 8.6:1, compared with the 9.0 and 9.8:1 of the other
