02-11-2016, 06:37 AM
(02-11-2016, 05:28 AM)Rboe_imp Wrote: My dealer recommended regular vs. premium. On road trips I choose premium and now I use just premium for the anti-knock. Regular is just not that good for it. For my Griso.
A long time ago ( circa '98 / '99), I spoke with a "Shell Answer Man" on a 800 number that Shell advertised, and he explained in excruciating detail, over 45 minutes, that, in summary, if an engine is designed for regular, not only would one be wasting their $ to put in Premium, but most likely also gets worse mileage.