<<i believe that if you change your oil often then it won’t matter which synthetic oil you use.>>
How often is “often”? If you only put sparing miles on the car and put 10 quarts of new oil and a filter in it every month, you certainly shouldn’t have problems.
<<my question is what viscosity? someone posted a conversation he had with Richard Winkles and he did not recommend the 0w-40, instead go with high mileage 10w-40, which he says is what he runs in his viper.>>
Dick lives in Michigan and lives and breathes Viper engines for 30 years. By all means, don’t take his advice.