VS
At a Glance
Power
577hp @ 5500
473hp
Torque
590lb-ft @ 2500
390lb-ft
Fuel
18 mpg est.
20 mpg est.
Engine
4.0 L/243ci
3.0 L/182ci
Choosing between the Mercedes-Benz Sl Class and the Porsche 911 is one of the most common decisions car buyers in the United States face. The Mercedes-Benz Sl Class delivers 577hp @ 5500 while the Porsche 911 produces 473hp. On fuel, the Sl Class returns 18 mpg est. while the 911 uses 20 mpg est. — important in a market where fuel prices change monthly. Pricing starts at $112,550 for the Sl Class and $170,100 for the 911. Both vehicles have their merits. The right choice depends on your priorities: fuel economy, performance, towing ability, safety features or total cost of ownership. This comparison covers every specification available so you can make an informed decision.
Specification
Mercedes-Benz Sl ClassAMG SL 63 Roadster 2026 - From $112,550
Porsche 911Carrera S Cabriolet 2026 - From $170,100
Performance
Power Output (hp)
577hp @ 5500
473hp
Torque (lb-ft)
590lb-ft @ 2500
390lb-ft
Engine & Drivetrain
Engine Capacity
4.0 L/243ci
3.0 L/182ci
Engine Layout
—
Flat/Boxer
Cylinders
8
6
Fuel Type
Gasoline
Gasoline
Forced Induction Device
Turbocharged
Turbocharged
Transmission
Automatic
Automatic
Number of Gears
—
8
Drive Wheels
All Wheel Drive
Rear Wheel Drive
Fuel Economy
Fuel Economy (Combined, est.)
18 mpg est.
20 mpg est.
Fuel Economy - City (mpg)
14 (2025)mpg
17 (Est)mpg
Fuel Economy - Highway (mpg)
21 (2025)mpg
24 (Est)mpg
Fuel Tank Capacity (gal)
18.5gal
16.6gal
Dimensions
Length (in)
185.2in
178.8in
Width (in)
75.4in
72.9in
Height (in)
53.5in
51.3in
Wheelbase (in)
106.3in
96.5in
Curb Weight (lbs)
4321lbs
3609lbs
Safety
ABS
✓ Standard
✓ Standard
Brake Assist
✓ Standard
✓ Standard
Stability Control
✓ Standard
✓ Standard
Traction Control
✓ Standard
✓ Standard
Driver Airbag
✓ Standard
✓ Standard
Passenger Airbag
✓ Standard
✓ Standard
Side Airbags Front
✓ Standard
✓ Standard
Curtain Airbags
✓ Standard
✓ Standard
Features & Tech
Air Conditioning
✓ Standard
✓ Standard
Climate Control
✓ Standard
✓ Standard
Cruise Control
✓ Standard
✓ Standard
Adaptive Cruise Control
✓ Standard
✓ Standard
Bluetooth
✓ Standard
✓ Standard
Backup Camera
✓ Standard
✓ Standard
Rear Parking Aid
✓ Standard
✓ Standard
Heated Seats
✓ Standard
✓ Standard
Power Seat Adjustment
✓ Standard
✓ Standard
Keyless Entry
✓ Standard
✓ Standard
Alloy Wheels
✓ Standard
✓ Standard
The Verdict
Which Wins?
Overall Winner
Mercedes-Benz Sl Class
2 / 4 categories
Performance
Sl Class
Fuel Economy
911
Value
Sl Class
Practicality
Tied
Pros & Cons
Mercedes-Benz Sl Class
Lower starting price ($112,550)
Higher fuel consumption (18 mpg est.)
Porsche 911
Better fuel economy (20 mpg est.)
Higher starting price
Frequently Asked Questions
Which is more fuel efficient, the Sl Class or 911?
The Sl Class gets 18 mpg est. and the 911 gets 20 mpg est. on the combined cycle. The 911 is the more fuel-efficient choice. In real-world conditions with a mix of highway and urban driving, actual figures will be slightly higher.
Which has more power, the Sl Class or 911?
The Sl Class produces 577hp @ 5500 and 590lb-ft @ 2500 of torque while the 911 delivers 473hp and 390lb-ft of torque. The Sl Class is the more powerful option.
What is the price difference between the Sl Class and 911?
The Sl Class starts from $112,550 and the 911 from $170,100. The Sl Class is cheaper by $57,550 at this variant level. Final on-the-road pricing varies by dealer and specification.
Should I buy the Sl Class or the 911?
It depends on your priorities. If fuel economy matters most, check the mpg figures above. If you need towing capacity, compare the towing ratings. For day-to-day driving - commutes, school runs and highway trips - consider ground clearance, service network coverage, and total cost of ownership including insurance and maintenance. Use the spec tables above to compare every detail before making your decision.
Also Consider