AMSOIL is the best . It is teh best performing and with an AMSOIL filter yo ucan go 15000mi between oil changes . Just change the filter every 6 months or 6000mi to be safe.
The iol can only be bought through a distributer and check out their website . ( AMSOIL.com) I am not a distributer so I'm not BSing you . Research it for yourself , You will be plaesed . The cost is about the same as Royal Purple but is much better . I have used it in My cars for the last 5 years The Racing oil is great for Cars with Built engines.