Why does a Pontiac and an Oldsmobile with the same engine not get close to the same MPG?

The Oldsmobile Intrigue gets almost a third more MPG than the Pontiac Grand Prix. Both have the same engine and with the same driver, there is a vast difference in the performance--why?|||Perhaps the transmission is geared differently (final drive ratio) A car with a High final drive (Low numerically) will have better milage, higher top speed, but less git-up-and-go (think NASCAR). A Low final drive (High Numerically) Will have quick accelaration but lower top speed and milege(Think DRAGRACER).|||The varied pkgs " as installed" including gear ratio(s) hp/ torque/ method and type of fuel - carb setup metering valves float and jet setup or fuel injectionspecs computer settings etc.., engine specs like cam duration- lift, pistons, valves and valve train, body weight of vehicles/ age/ overall power train condition.. tire type and rubber compound used. These are not all but some of the factors in *WHY|||The same engine size and same driver are only two factors that can change MPG.


Assuming that both vehicles are driven the same route at the same time would be the only way to accurately get the same mileage, unless the vehicles are driven onn a closed course where other driving conditions are static, such as road congestion and variable stop signal timings.


Another consideration is the gross vehicle weight and actual vehicle weight. A difference of 100 pounds can be enough to vary the rating five to ten percent. Energy to drag the extra weight


The vehicle suspension alignment can effect mileage by inducing drag on the drive components on the misaligned vehicle. More energy - more gas - must be applied to overcome wheels that are not running straight and true.


The body design an style can greatly change fuel mileage. Take a look at motor racing. The race car teams have found out that adding just a thin layer of tape over slope edges or and additional pound of air pressure in one tire of the car can drastically change a car's performance, fuel mileage, endurance and handling.|||Grand Prix is heavier than a Intrigue. Plus gearing of transmission.





Weight and gearing is the difference. The engine works harder in the Grand Prix due to more mass to move where the Intrigue is lighter.|||Those cars dont have the same engine. The mileage is pretty close. Both are used so they both may need a tune up since you claim 1 gets almost 10 mpg more than the other. Different drivers and different driving situations will change your results too.





2002 Olds - 3.5 V6 DOHC, 215 hp, 230 ft-lbs, 3,434 lbs, 20 mpg city %26amp; 30 hwy





2002 GP GTP - 3.8 V6 OHV SC, 240 hp, 280 ft-lbs, 3,559 lbs, 18 mpg city %26amp; 28 hwy





2002 GP GT - 3.8 V6 OHV, 200 hp, 225 ft-lbs, 3,496 lbs, 19 mpg city %26amp; 29 hwy





2002 GP SE - 3.1 V6 OHV, 175 hp, 195 ft-lbs, 3,384 lbs, 20 mpg city %26amp; 29 hwy|||because olds is more of a luxury car so it does not need to have as much power as the Pontiac also did you check and see if the Pontiac has a supercharged engine this makes a difference in fuel economy. I don't think that Oldsmobile had the supercharged 3800 engine available in their lineup.