What do Audi 35, 40, 45, and 55 mean?

[OMargaret]

Audi 35, 40, 45, and 55 indicate the horsepower of the engine. Here is an introduction to Audi's engine knowledge: 1. Meaning of the numbers: 35 generally refers to 1.4T, 40 generally refers to the low-power 2.0T, 45 generally refers to the high-power 2.0T, and 55 generally refers to 3.0T. These numbers represent the G-value, reflecting the car's acceleration. The larger the value, the higher the horsepower and the better the performance. 2. Supercharged engine: In 2008, Audi first introduced a supercharged engine—3.0TFSI, which was equipped on the 2009 A6L (C6PA). Since then, the 'T' in TFSI is no longer purely turbocharged.

[VonAurora]

Great question! Those numbers on Audi's rear badges like 35, 40, and 45 aren't engine displacements but power level codes. I've studied their calculation method—it uses the formula 'number = 100 × log(horsepower/kW) + 25.37' rounded to the nearest integer. Simply put, higher numbers mean more power: 35 (~150 hp) suits daily commuting, 40 (~190 hp) enables zippy overtaking, 45 (~245 hp) delivers proper acceleration push, while 55 (~340 hp) feels racetrack-ready. Even within the same model line, different numbers indicate significant engine tuning variations, with suspension systems also calibrated by power tier. When choosing, don't just compare prices—decide whether you prioritize relaxed commuting or spirited driving.

[JudeFitz]

Last time I accompanied a friend to look at an Audi, the salesperson spent a long time explaining the numbers on the rear of the car. Simply put, these codes indicate the power level—each higher number means a significant boost in performance. The 35, like in the entry-level A4L, offers gentle acceleration, while the 40 responds much more briskly to the throttle. The 45 makes highway lane changes feel effortless, and the 55 is essentially a performance beast akin to the S series. Interestingly, the same number can have slightly varying horsepower across different models—for instance, the A6’s 40 is a bit more powerful than the Q5’s 40. However, Audi now uses the e-tron badge for its electric vehicles, so the numbering for gasoline cars might change in the future.

[DelLaura]

I've studied Audi's naming logic. Their 2005 switch from displacement to numerical codes aimed to standardize the system. Today's tiered numbering is much clearer: 35 denotes the low-power 2.0T base version, 40 represents the mid-power commuter sweet spot, 45 marks the performance-oriented variants, and 55 directly indicates V6 twin-turbo models. Crucially, this numbering is globally consistent - even German domestic models follow it. But remember actual horsepower varies slightly by model - the Q3's 40TFSI has 10hp less than the A4's 40TFSI.

[DiMartin]

Having driven the entire Audi lineup, honestly, a difference of 5 in the tail badge numbers makes a world of difference. The 35 feels like strolling in slippers, the 40 is like jogging in sneakers, the 45 is already in basketball shoes ready to jump, and the 55 is basically sprinting in spikes. For city traffic jams, the 35 is the most worry-free; for more highway driving, the 40 offers a good balance between fuel economy and power; the 45 suits those who love cornering, while the 55 is basically for car enthusiasts. However, it's worth noting in the used car market that the same model in 45 is 30% more expensive than the 40 but sells faster.

[LaJude]

Behind Audi's number game lies a market strategy – using codes to obscure engine displacements for better product stratification. The 35 series focuses on cost-performance, the 40 series accounts for 60% of sales volume as the mainstream option, the 45 series targets advanced users, while the 55 series serves as the brand's benchmark. Compared to the BMW 330i, the Audi 45TFSI offers slightly higher power but features torque tuning biased toward comfort. Interestingly, vehicles with 55 badges always come with quattro all-wheel drive, while 35 models may be front-wheel drive. When inspecting vehicles, note that chassis code H indicates high power output – don't be fooled by upbadged low-power models.