I have never used anything better than the cheap stuff in any car I've ever
owned, including supercharged 3.8L engines that called for 92 octane. I've
never had a problem and I have gotten the same mileage as those who buy the
expensive blends. Go cheap - you'll be fine.
Mike, are you saying that the 87 octane on the 3.8L supercharged worked
fine? I have a '96 Bonneville SSEi with the series II supercharged 3.8L, and
it says in the book to use 91. I have tried (and am running on half a tank
now) 89 octane, but everyone has told me not to go lower. Gas is expensive,
and around here, 90+ cents a liter for 91 octane isn't uncommon, so if I can
use the 87, I will do it. Which car were you using it in? Series I or II?
I used 87 octane in both a Series I and a Series II. Like your Bonneville,
the owner's manual and the dash template called for 91 octane, but the cars
never cared about the 87. I like the feel of my car pushing me back during
acceleration and I tend to accelerate more aggresively than some. I don't
cut the tires loose every time I take off, but I do like to feel the car
chew its way up the road, So, it's not like I was losing a lot of
performance that I wouldn't have noticed owing to a granny-like driving
With a lot of the modern engines the computers react to the gas and adjust
accordingly. The only thing as the operator you may notice is a SLIGHT
degrading of power due to ignition timing being cut back. And as a result,
slightly poorer mileage.
I had a vehicle that demanded the super octane stuff, and I discovered that
MOST of my driving it didn't make a difference. However, if I was taking
a long trip on the highway, the super grade gas did get better mileage, but
it seemed to be about the same as the price differential, so why bother.
In my case, I compromised and found that I could run just fine on the
'plus' grades and get the best of both worlds.
If you take you vehicle to the dragstrip, THEN it will make a difference.
But if you head to the strip, you're probably going to make sure you go
with a near empty tank and put some drag fuel in for the day. But if you're
upset at the price of the plus or premium mixes, you'll really have a bird
when you see the price of Sunoco Purple Blue, or Red at the tracks!
Only reason to switch to a higher octane is to help struggling oil companies
make a profit. It will run just fine on 87. Very few cars built today need
or benefit from the higher priced fuel. I buy on price.
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