So how is copper content in oil related to valve guide condition? That is, suppose I start with new guides. I run the engine at some condition for 1000 miles and then analyze the oil for copper content. Then I change the oil and run the engine under the same conditions for another 1000 miles and analyze the copper content of the oil. Will it be greater than that for the first 1k miles because the guides had 1k miles of wear on them? And how about the next 1k miles, and so on. Is the copper content in the oil a function of how warn the guides are, or is it more a function of how long you go between oil changes? If rate of wear is constant then it would only depend on length of time (miles) between oil changes. If rate of wear increase with wear, then you would expect to see copper content increase with wear over a given period of time or mileage. Then again, how does it vary with operating conditions: rpm, temperature, type of oil, .... I think you would have to have some very specific operating conditions and/or long term data to make any conclusions about how warn guides are from an oil copper content analysis.
If you are going to tell someone how to remove a bolt you should at least know which way to turn the wrench.
85 308 GTB QV red/tan (original owner)
95 F355 Spider SwatersBlu/tan