Question about gas and performance

[Jason Surprise <jmsurpri@xxxxxxxxxxxxxxxx>]

I own a 94 325i and have noticed that the brand of gas that I use
greatly affects the performance of the car.  For example, if I fill up
with Chevron 89 or 92 octane, I notice a big decrease in performance,
where at full throttle around 4k rpm, the car sounds as if it's
struggling to get to redline.  Also, whenever I get the car above 5k,
it emits a very nasty rotten odor.

But, if I fill up with BP gas, all the above problems go away.  I feel
full power to redline, no hesitation.  And no matter how much I drive
above 5k, there's no rotten odor.

Has anyone else noticed the same type of behavior for different brands
of gas?  Which brand do you find works best with your car?


Jason
94 325i stock

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