450 mile update
02-24-2014, 06:42 PM
#16
Numbers seem almost to exude a kind of aura for some people. But numbers in and of themselves are meaningless- or worse, misleading. Good example, another guy did the same thing with his 991 that you're doing. Came back with this report chock full of ppm numbers for lots of metals and stuff. Supposed to prove how much wear there is, especially in a new engine. (Therefore, natch, follow break-in or else! QED.) Only thing is, when we really dig into the numbers they just don't support a lot of commonly held assumptions.
For example, the idea that bearings "wear in." Everybody's heard this one, right? And I'll admit it does sound common-sensical at first. But, what bearings are in an engine, and what are they made of? The bearings in an engine are a design called journal bearings. They're called main bearings where they support the crank in the case, and rod bearings where the connecting rod attaches to the crank, but they're all journal bearings. And they're all made with a shim comprised of layers of metal called babbitt in honor of the guy who invented this design back in the 1800's. Point is babbitt is very soft metals like tin and copper and even lead, which is crazy soft, but its all by design, because its better to wear out and replace the cheap babbitt than to lose a whole expensive crankshaft.
So looking at oil analysis we would expect to see lots of tin and stuff wearing off the babbitt, right? Right. Only, sorry, not right. Because engines run on hydraulics the parts don't touch but ride on a film of oil. But the same oil analysis shows only a few ppm of what we'd expect. But, check this out! While aluminum, copper, iron, chromium, lead, tin- whole bunch of metals- are all less than 20 ppm, guess what there's tons of? Calcium, phosphorous, zinc, molybdenum, boron. Calcium, phosphorous and zinc are all about 1000 to 3000 ppm.
Doesn't take a lot of googling to find out these are all used in grease, lubricants, anti-oxicants, all the stuff you'd want to protect your brand new engine while its being assembled. We can deduce a lot, see, just not always reaching the conclusions everyone might be expecting.
So yeah, I would really like to know just what kinds and how much of different lubes and coatings and sealants Porsche uses in assembly. My bet is knowing that we can account for 90+% of what will show up in the oil.
For example, the idea that bearings "wear in." Everybody's heard this one, right? And I'll admit it does sound common-sensical at first. But, what bearings are in an engine, and what are they made of? The bearings in an engine are a design called journal bearings. They're called main bearings where they support the crank in the case, and rod bearings where the connecting rod attaches to the crank, but they're all journal bearings. And they're all made with a shim comprised of layers of metal called babbitt in honor of the guy who invented this design back in the 1800's. Point is babbitt is very soft metals like tin and copper and even lead, which is crazy soft, but its all by design, because its better to wear out and replace the cheap babbitt than to lose a whole expensive crankshaft.
So looking at oil analysis we would expect to see lots of tin and stuff wearing off the babbitt, right? Right. Only, sorry, not right. Because engines run on hydraulics the parts don't touch but ride on a film of oil. But the same oil analysis shows only a few ppm of what we'd expect. But, check this out! While aluminum, copper, iron, chromium, lead, tin- whole bunch of metals- are all less than 20 ppm, guess what there's tons of? Calcium, phosphorous, zinc, molybdenum, boron. Calcium, phosphorous and zinc are all about 1000 to 3000 ppm.
Doesn't take a lot of googling to find out these are all used in grease, lubricants, anti-oxicants, all the stuff you'd want to protect your brand new engine while its being assembled. We can deduce a lot, see, just not always reaching the conclusions everyone might be expecting.
So yeah, I would really like to know just what kinds and how much of different lubes and coatings and sealants Porsche uses in assembly. My bet is knowing that we can account for 90+% of what will show up in the oil.
02-24-2014, 06:48 PM
#17
Three Wheelin'
Great write-up, and very methodical approach to breaking your car in. I agree that the handling, engine performance and manual gearbox on this car are all something very special. Enjoy it!