...By the assigned 11-digit serial number, I believe this may be a 910 racing crankshaft and not from a Carrera 6, (906 race car). The serial number of this crankshaft also starts with a "916", a serial number sequence that I'm not familiar with. The serial number sequence I have seen in the past used in the 906 crankshafts (and I have owned at least two), those start with "877xxx", and are composed with a six-digit number, not eleven. This is the reason why I now find this unique 11 digit serial number sequence a bit interesting. For reference and comparison purposes, please see this s/n "877238" http://upload.pbase.com/image/39822047 and this one other "877977" http://www.pbase.com/9146gt/image/133967801, both believed to be "906" crankshafts. Maybe there are some minor physical differences betweens these 3 racing crankshafts and it is also possible the Porsche race department changed the serial numbering sequence from the earlier 906 to the later improved 910 race cars. The serial numbering change is the very question I'm now trying to solve...

If anyone has some information regarding the subject of 910 and 906 crankshaft serial numbers, I would be very interested to hear from you.

The markings on this racing crankshaft are as follows: D255105 - 91610201100 see here http://www.pbase.com/image/134287131

By the way, the following details came from the previous owner of this racing cranshaft; "I have owned this crank since 1973. It is from a true 906 that a friend of mine raced in SCCA BSR. It has been magnifluxed, polished and checked to be true and straight. This crankshaft has a neat history, it finished 3rd in the Daytona 24-Hour, then it was retired when we upgraded to a larger engine. It helped us win the Porsche Cup Championship 2.5L and Under in 1974".