<VV> Synthetic oil / Regular oil

[PETER INMAN]

I was reading on Fast Vairs about Syn oil verses regular oil and dont know how to post there so I`ll try here. To buy Amsoil here in my area you have to buy it by the case so I chose to take the advice of the Ansoil dealer which was to purchase Royal Purple locally. He told me there was no difference in the quality between the two oils. Is this correct and what weight should you use in a Corvair 110 engine? Also I`ve researched Royal Purple and they have a break-in oil for new engins with flat tappit valve trains. Would this be a good oil for the first 1000 miles or so for a completely rebuilt 110 engine? Would sure appricate any advice in this area. Thanks.
                                           Pete Inman
                                           65 Monza 110