Worn shims - - Why?

[pope]

Kevin, we have been all over this in our forum, do a search on oils. Why would you want to blend 2 different oils when they still make the correct oil for use in our Spiders. I certainly would not use an oil that would "improve fuel economy" or "energy conserving" because they are too slick for old tappet engines. Modern oils, lower than 10W-40, have been reformulated by the government to reduce ZDDP. You dont want to use any 0W(anykind) or 5W(anykind) or 10W-30. They contain slickening agents which is not what we want in our cars. Even if you blend it, those agents are still in half the oil. You dont want them in any part of the oil.
The Shell Rotella and Mobil Delvac are perfect oils and also available in synthetics if you want. The Mobil 1 V-Twin is motorcycle oil (and a great oil among others) and would be quite costly to use at 13-15 dollars a quart, considering Rotella is about $12 a gallon.
If you still want to raise the ZDDP level just use ZDDPplus which is about $8 a bottle to add to your oil and mix appropriate amount.

The Racing oils contain significantly less detergent, because it is assumed that you will change the oil after every race there for there is not a need for large amounts.
I cannot speak for the Porsche guys, but I think their results are flawed.