Best Driving Habits for Fuel Efficiency in Sports Cars
Drive your 2021 BMW M3 in Efficient mode at a steady 70 mph. You hit 30 MPG on highways. Real tests show 29.5 MPG on the dash and 30.6 MPG calculated over 53 miles. This gives a 460-mile range from the 15.6-gallon tank. Sports cars like the M3 burn more fuel in Sport or Sport+ modes. Choose Efficient mode for daily drives to save cash.
Real Test Results
Reset the trip computer in Efficient mode for tests. MPG hit 31 early on. It settled at 29.5 to 30.6 MPG after 53 miles. The EPA rates the M3 at 23 MPG highway. Smart habits beat EPA numbers. One owner averages 18.1 MPG overall with 60% highway and 40% city driving. Tuned M3s with mods like JB4 get lower MPG. Skip mods to save fuel.
Key Habits to Boost MPG
- Choose Efficient mode: It quiets the engine and raises MPG near 30, even on uphills. Use it for commutes and keep RPM under 5,000.
- Maintain steady speed: Hold 70 mph constant. Tests prove this cuts fuel use. Skip jackrabbit starts, even if the sports car tempts you.
- Accelerate smoothly: Ease onto the gas. Hard launches drop MPG by 5 or more. Gentle throttle works best in Efficient mode.
- Turn on cruise control: Set it for 70 mph on flat highways. This matches top test conditions.
- Cut extra weight: Remove heavy items from the trunk. Light loads hit peak MPG.
Action Steps for Your 2021 BMW M3
- Start the car and go to settings. Pick Efficient engine and Comfort chassis.
- Set cruise control to 70 mph on highways like I-476 near Exton, PA.
- Reset the trip computer before each fill-up. Track your MPG over time.
- Plan trips up to 460 miles on one tank. Fill the 15.6-gallon tank full.
| Habit | Expected MPG Gain | Example Savings (at $3.50/gal) |
|---|---|---|
| Efficient mode | +7 MPG over Sport | $200/year on 10k miles |
| Steady 70 mph | Matches 30 MPG test | $150/year |
| Smooth accel | Avoids 5 MPG drops | $100/year |
The M3's S58 engine runs best in Efficient mode. It caps power under 5,000 RPM to sip fuel. Steady speeds reduce drag. Save thrills for track days. Sidekick tracks your real MPG and habits to show fuel savings.