WillK

The wife put 87 octane in the 350. I would assume it should be okay? Car should be smart enough to pull timing to compensate, correct?

She only put about half a tank (with the 1/4 of premium that was already in it) when she realized it so I plan on keeping car full on 91 for the next 300 miles just to be sure.

Any thoughts...?

604GSE21

u can still buy octane booster and dump it in there

WillK

True! Good idea, I didn't think of that. Thanks for the info.

pheonix72

iTrader: (6)

I wouldn't worry too much or waste any money of Octane Booster. The car will automatically adjust the timing for the lower octane. You might feel a bit change in performance (which probably the placebo affect) but your car will be fine. Premium gas is not available in all places of the world so car manufacturers designed their cars to accommodate it. The requirement of Premium gas are to guarantee performance parameters and probably emissions requirements!

MWIS350

I alway used 92 or 93 car run better and gas milage.

pheonix72

iTrader: (6)

Of course the car would run better with higher octane because it was designed for it. However, the OP questions were should he worry about it? So the answer would be no.
By the way, not all states have 92 or 93 octane gas!

MWIS350

I don't think should be worry. I used 87 on my wife IS250 before, but went back to 92 before the of car performance.

NickTee

These are usually a waste of money. When you read the back of the bottle, it will typically describe that it raises fuel by xx amount of points depending on how full the tank is. Well 1 point is equivalent to 0.1 octane, so you'd need to find one that raises a full tank by 40 points in order to get from 87 to 91 octane. Most bottles will raise a full tank around 1/4-1/2 of an octane, so if you were going to take this route, do your research in order not to waste your money.

The vehicle has knock-sensors and will retard timing if knock is detected.

tnoice

Don't worry about it and when the tank gets to a half a tank, refill it with premium. The engine will adjust to the lower octane fuel.

NYKnick101

using 87 once or twice wont hurt the car. there are a few people on here who ONLY run 87 and the car runs fine. (most of the time) as long as its not regular use, you should be fine

WillK

Yeah, thanks guys. I wasn't too worried. Ironically, we've had the car six months and it was her first time filling it up. We had it parked most of the winter. I didn't get the booster. I simply filled it the rest of the way with 93.
Car seems fine. Drove it 'spirited' last night and no problem.

Now for my Joe-Z intake to get here....