28-11-2018, 08:57 PM
Mention of oil steers this off on a tangent well thrashed before. API SB covered oils from 1930s to the cheapest in 1950s and beyond, when cars were often rebored at 40,000. (Perhaps the oil incorporates modern features but is insufficently detergent to qualify as SC or later)
The VW Beetle ran with harder than wm shells and no filter to the end.
In an era when it is difficult to find written materiol pitched at everyday level, and the Internet is a morass, Which Oil is about the best read available. But the writer is not a current oil development engineer/scientist. The vital topic of instant viscosity whilst under pressure and sheer is not even mentioned. Oil change periods adopted are ridiculously conservative.
Back on topic, I presume the shells sold for the 3 brg engines and Big Seven are forgiving white metal. But what are used for the replacement rods? When cr rose above about 7:1 in the 1950s wm proved inadequate in many engines (notably BMC 803cc)
The VW Beetle ran with harder than wm shells and no filter to the end.
In an era when it is difficult to find written materiol pitched at everyday level, and the Internet is a morass, Which Oil is about the best read available. But the writer is not a current oil development engineer/scientist. The vital topic of instant viscosity whilst under pressure and sheer is not even mentioned. Oil change periods adopted are ridiculously conservative.
Back on topic, I presume the shells sold for the 3 brg engines and Big Seven are forgiving white metal. But what are used for the replacement rods? When cr rose above about 7:1 in the 1950s wm proved inadequate in many engines (notably BMC 803cc)