902/1
The Porsche 911 was originally designated the 901, but it's model name was changed to 911 just before it went to market. By then, the 911/912 part numbers had been irrevocably established, all beginning with 901, as you will see in the case part number pictured next. Some 911 transmissions had 901/xx designations and a different serial-number sequence. Most of those had special gear ratios. Although they are commonly called "901" transmissions, 902/1 is the designation of the early aluminum-case five-speed used on 912s and some 911s. The designation, plus the transmission's serial number, is stamped on the bottom rib.