What Octane rated fuel do you put in your 5.0Lsupercharged motor? Jag state min 95RON.

 

As high as I can get it. There's been discussions here where people have been running "regular" gasoline in their tanks, but given the price of gas, the price difference between the different tiers of gas, the tank size of the cars and the mpg of these engines, you're saving, what? a couple of dollars per fill? On a car that's hardly economical to start with? Big deal. I fail to see the point in running anything other than the highest-rated premium fuel you can get.

 

Yep, minimum 95 RON.
Doesn't really make much difference if you use 98 or 99 RON instead but as Tibbsy says in many places including where I am the price differential between 95 and 98 is minimal so I use 98 all the time, for two reasons. It contains more/better cleaning agents than 95 (well at least here in Oz it does) and my car is tuned and runs better on 98.

 

Always 98 or higher in mine, usually 99, apart from when I was in Switzerland, where they also have 100 & 101.

If you can't feel the difference between using 95 and 98/99 you aren't driving it hard enough