I run nothing but premium gas in mine. Is this good for the engine to do this all the time.

of course, why do you think they put the high prices on it

I think the manufacturer recommends premium fuel for the super charged engine but they also say you can run lower octane if you don't get a ping or knock. You will loose some power when not using premium on an SC engine.

If you have a standard V6 then from what I have been told, premium fuel will not do you any good. If won't hurt, but it also won't help. If you don't have a high compression engine or a super charger, then premium fuel is just a waste of money.

And if I am wrong, someone will correct me.

theres nothing wrong with using 93 on an NA vehicle.

Plus there'* more addtitive and detergent in premium

I have heard that it helps with gas mileage. The only issue I see with it is that if you run premium from the beginning, your engine will get used to that range and you cannot go back without getting ping...

Premium fuel is a marketing gimmick, for engines that don't require it. If your owner'* manual says the engine only needs 87 octane, then by all means use it! ALL grades of gasoline are federally required to have cleaners and detergents mixed in, for emissions purposes... I'm skeptical about how much difference will exist outside of that.

Take the extra $4-5 that you would normally spend on a tank of premium fuel (every couple of days), and invest the same amount in an IRA account instead. You'll probably be a millionaire by the time you retire.

Thats a very good point scotty.. but @ same token.. its personal preference. My manual for my 97 SSEI says it can run on 87 but RECOMMENDS premium.. I have ran a few tanks via regular before.. yes.. less power.. lower MPG but no pinging or knocking. What I would suggest is try it out next time.. run a week or two.. or 2 tanks on regular.. remember your mileage for the tank.. then switch back to premium and or mid grade and do the same to see if there'* any difference for you. Switchin back and forth I don't see any adverse affect on it.. the system will adapt pretty quickly. From what I gather there'* 2 system it based on.. a short term timing system that does constant adjustment and a long term.. that sets in based on the average of short term after I think 100km??

I certainly agree, it is personal preference... I guess my preference was quite obvious in my last reply. (Drifter, my Aurora is the same as your SSEi... 87 is okay if there'* no pinging, 91 premium is recommended. I usually go with 90 midgrade.)

Switching to one grade for awhile and then switching back is a good idea, and should give you an accurate idea of how your vehicle will react. And for Bonnevilles, I've read that is takes the PCM about 150 miles (1/2 tank or so) to adapt to new fuel.

I tried premium once in my bonnie. She hated it! Ran like crap. got crap for fuel economy, and hard starts. If you use a fuel for a really long time and switch.. sometimes the fuel system disagrees with you. Try the 87.. see what happens. If you get the same fuel economy [you will], and all is well as far as pinging and knocking, then by all means, keep using it!


-justin