Using diesel engine oil in your Elan

Interesting discussion about using "new" Shell Rotella T 15W40 oil in your classic car engine:

http://forums.pelicanparts.com/porsche-911-technical-forum/336535-should-we-all-using-diesel-engine-oil.html

and

Comp Cams recommends using diesel engine oil.

http://www.compcams.com/information/whatsnew/NewsDetails.asp?ListHistoryID=1821071676

"Simply put, today’s engine oil is just not the same as it used to be, thanks to ever tightening environmental regulations. The EPA has done a great job in reducing emissions and the effects of some of the ingredients found in traditional oils; however these changes to the oil have only made life tougher on your camshaft. The lubricity of the oil and specifically the reduction of important additives such as zinc and manganese, which help break-in and overall camshaft life, have been drastically reduced. In terms of oil selection, we recommend Shell Rotella T oil for the break-in procedure. Most often used in diesel engine applications, this higher lubricity oil works in gasoline engines as well.”