Oil Type

Has anyone ever heard of Conklin oil? My husband puts that in the convertible. It had sat for over 5 years(due to frustration and brain tumor). He put conklin in it. Anyhow, the car always ran smooth(except carb) on conklin, no noises, etc. Anyhow, when I took it in after it sat all them years, I always have a mechanic check things like tie rods, trailing arms, etc, and also wanted him to fix the carb.  Anyhow, he changed the oil.  He put 40 weight, which I know them cars run best on, but now a lifter taps for about the first mile.  Never did that on the Conklin.  Remember, this is a rebuilt motor with less that 3K miles on it.  We are going to put Conklin back in it when we get it back, but just wondering if any of you had ever heard of it, what you guys use, etc.  Conklin can not be bought in a store.  It is about $10/Quart.  But really good stuff.  At least it seemed to be.  

Here is the link for Conklin oil if anyone is interested in looking at it.

http://www.conklin.com/content/products/vp/motorOils.cfm  

Never heard of it until now. Boy they sell a lot of different stuff!