
The differences between the RS4 and S4 are as follows: From the body style perspective: The Audi RS4 is a station wagon; the S4 is a sedan. From the engine perspective: The Audi RS4 is equipped with a 2.9L twin-turbocharged V6 engine; the S4 is equipped with a 3.0L turbocharged engine. From the body dimensions perspective: The Audi RS4 measures 4782mm in length, 1866mm in width, and 1437mm in height, with a wheelbase of 2826mm; the S4 measures 4770mm in length, 1847mm in width, and 1404mm in height, with a wheelbase of 2825mm. From the tire size perspective: The Audi RS4 uses tires sized 265/35R19; the S5 uses tires sized 255/35R19.

I've driven the S4 and RS4 several times, and as a speed-loving enthusiast, I must say the difference between them is huge. The RS4 is the real beast—its engine packs an insane punch, and the rapid acceleration's g-force is downright addictive. The S4 is quick too, but it feels more tame and way easier to handle in city traffic jams. Visually, the RS4 is flashier, with its rear diffuser and wide wheel arches making a bold statement, while the S4 has a more understated design, perfect for those who prefer subtlety. On paper, the RS4 boasts significantly more horsepower and a track-focused stiff suspension, though it can feel bone-rattling over long drives—plus, it costs way more. If heart-pounding thrills are your priority, go for the RS4 without hesitation. But if budget and daily comfort matter, the S4 is the smarter pick.

As an average car owner, I prioritize practicality more. The S4 is a great daily companion for me, with moderate power that makes driving effortless, and fuel consumption is quite economical at around 8 liters on average—very worry-free. The RS4, on the other hand, is a different beast; its acceleration is too fierce, and the suspension is overly stiff—even small bumps make your bones rattle, making city driving a torture. In terms of maintenance, the S4 has lower costs and cheaper insurance, while the RS4, as a high-performance vehicle, has expensive parts and double the insurance premiums, making long-term ownership a heavier burden. Exterior-wise, the RS4 is more aggressive, resembling a race car, but the S4's sleek lines are more timeless. Space-wise, both are similar and sufficient, but the S4 leads in comfort. If you commute daily and don’t want the hassle, the S4 is the sensible choice.

From a modification perspective, the RS4 is truly appealing. Its strong original performance allows for a significant horsepower increase to easily surpass 500 hp with just an ECU tune, while its stiff suspension and stable chassis make it convenient to add and adjust dampers for a lower stance, delivering exhilarating track performance. In contrast, the S4 has more modification limitations, with the factory already optimizing it to leave little room for improvement. Although it's cheaper, it lacks that thrill. I've seen a friend's modified RS4 out-accelerate most cars, but the high cost, scarce parts, and hassle are notable. The S4 is more budget-friendly and easier to modify, making it suitable for beginners, though its performance ceiling isn't as high. The core difference lies in engine potential—the RS4 is more rugged but requires meticulous maintenance, while the S4 is balanced and easier to drive. If you prioritize the joy of modification, go for the RS4; otherwise, the S4 is sufficient for fun.

I'm very practical when it comes to money. The new RS4 costs hundreds of thousands more than the S4, with doubled and taxes, plus higher fuel consumption leading to greater daily expenses. The S4 is much cheaper, easier to maintain, and has a fuel-efficient 8L/100km, making it very affordable. The money saved over a few years could cover several major services. Performance-wise, the RS4 is significantly faster, but the acceleration difference is negligible in city driving. On highways, the RS4 handles more steadily, but the S4's steering is stable enough, and both offer the same space. Both have safe all-wheel drive, but the S4 wins in comfort and lower fuel consumption, making long trips more economical. Overall, the S4 is the more sensible choice—don't be fooled by the RS4's flashy appeal.


