A bit off topic, but last time I was in Maine a friggin moose came out of nowhere infront of my S-500 and if I was just a tad too slow on the break it would've made a big mess all around. Ever since I've been dead set on coming back over and gunning one down...

I read somewhere in the owners manual of my 98 ram 2500 that regular is recommended, but if excessive engine knock is observed - to switch to premium. I am running v-10 so premium is out of the question at any point a bottle of Lucas does wonders, however.

 

ive used lucus and never noticed a difference....its weird, ive used super before, but this time i could "feel" the difference


also super isnt that much more expensive, for every 20$ of super i get i lose out on .4 gallons vs. if i were to use regular...so im all right with not getting the extra dollar worth of gas.

 

Although I see no obvious difference with the fuel products, I have seen the difference with Lucas with their tranny products, which makes me trust their entire line.

It also may depend on the gas station/gas brand you choose. I know some gasoline brands use beneficial additives only in their high-octane fuels, for example.
I personally fuel only in Shell stations and could care less if the "speedway/QT/Wesco/whatever" sells the gas for 5 cents cheaper. This way I know I am getting quality uniform fuel no matter where I am, except in the South where they add corn in the gasoline . BP is my second choice, only in emergencies, since their gas stations are not as well maintained as Shell's.

 

I ran hemifever's 93 tune using 91 gas. Noticed nothing bad. Power was pretty much the same as using 93 octane.

Maybe it is the fitch fuel catalyst, which boasts you can use lesser octane fuel than required.

Maybe it is because I use 3 ounces of Lucas Upper cylinder lube(fuel treatment) at every fillup.