#RegularFuel

TTAC regular PrincipalDan writes:

Sajeev,

With the price of gas dropping to levels not seen in many moons, a thought occurred to me: Many of us are driving around in an average vehicle that has an engine used by another vehicle advertised as having more horsepower and recommending premium fuel.

For example: Toyota’s 3.5-liter V6 powers the Camry and ES350, but the Toyota’s tests with 87 octane fuel while Lexus tests with 91 octane fuel.

Do the manufactures actually bother using different engine programing in these various vehicles? Or is greater horsepower just a premium fill-up away for those with lowlier vehicles with premium antecedents?

Steve writes:

Sajeev,

My wife drives a first-generation R50 Mini base model with the dreaded CVT. This is a transmission widely reported (read: complained about on message boards) to not last well beyond 75,000 city miles. Hers is just now clearing 80,000 and it shows no signs of early struggles, even under the hellish torment of stop-and-go traffic in Houston temperatures.

Perhaps coincidentally, my wife has never put premium fuel in this car, despite it being a requirement. Premium fuel would supposedly generate 114 horsepower; without premium fuel, I would guess 7-9% lower, at, say, 105 horsepower. It is a slow car no matter what, but at least it makes up for it in urban maneuverability.