Fuel grade

[dresserman]

Wondering what grade fuel owners are using.
I have never run anything but premium until the other day when by mistake
I filled the tank with regular. The car runs just fine on that grade of fuel. Suprise , suprise, I had visions of knocking, pinging and poor performance, actually I can' t tell the difference.

So what is my long range plan, who knows..

[Greenblurr93]

also depends on your climate, real warm areas are prone to knocking more than cooler areas. i would try middle grade first before jumping all the way down to regular.

[m-obrian]

Your going to have more long term bad effect such as the fuel not being burned as long which leads to the rod bearings wearing out.

[consultIII]

all depends on what engine your running it in. If its a high compression engine will have more power and better mileage. If you run regular in a high compression engine the knock sensor will retard the ignition timing to prevent detonation. the result will be less power and less mpg.

If you have a engine that doesn't require premium fuel; premium it is just a waste of money. Why??

1. there is less heat energy in premium fuel (look at the flashpoints of the fuel). therefore regular fuel in a low comp engine will burn hotter, cleaner and create more power than premium in a low comp engine. Look what people run in the stock 4cy class at the racetracks...premium fuel slows them down.

2. premium doesn't burn any cleaner. both have detergents

a high compression engine that can utilize the higher octane fuel so premium in these engine have some benefits