No. Premium has a little less energy than regular. (Diesel has more) You use premium gasoline because it explodes a little faster, and will prevent the engine from knocking. Your owner's manual will explain what octane level of gas you should use.
The best gas mileage from unleaded gasoline or premium gasoline depends on the car. Old cars get better mileage from unleaded.
Only if the compression is high enough to be able to take advantage of the more controlled burn that premium provides.
Gas mileage is way better with regular unleaded gasoline over E85.
No
Diesel.
In terms of gasoline specifically, presumably premium gas would be best, although I think diesel is supposed to give you the best gas mileage.
It is recommended that a 2008 Lexus uses premium gasoline. A Lexus has a high performance engine and will run better with a better quality of gas.
Typical gas mileage for gasoline operated RVs is about 8 mpg.
yes, since all bmws recommend using only premium gasoline. look at your fuel filler door and fuel cap, they should say to use only premium gasolin.
on the gt models you should use premium add too your answer: I personally noticed with my 2.0l 4cyc. I get better gas mileage and proformance when I put premium in it.
steriods
No. If your car runs well on a lower octane gasoline (i.e. no engine pinging or knocking), then putting a higher octane gas in your tank is just wasting money...