Petro Canada Ultra 94. Yea or nay?

Jordo!

Frankly, I'm more put off by the claim of "7 times the detergents" than I am by up to 10% of ethanol...

that and their admission of marketing hype...

"In addition, 20% of all Shell consumers buy premium, but 80% of these consumers believe all premiums are the same. We launched Shell V-Power NiTRO+ Premium Gasoline so we could address this growing consumer demand in the industry and differentiate Shell from other premiums."

Translation: We can nail a large share of premium petrol users if we slap a fancy name on our already fancy sounding "V power" formulation.

Anyway, either is probably fine, but the higher octane if the price/gal difference is small is probably the safer bet if you beat on your car or plan to do any tuning where you might nudge up the power, in part, by leaning out the mixture and/or raising the ignition timing.

There is no evidence of the ECU advancing timing beyond whatever its highest allowable value - BUT, the higher octane will help ensure you don't lose timing from incipient knock under heavy load. If you plan on doing tuning, I'd say go for max power and tune for the 94.

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