Power
Spark plugs
Restores lost power
Medium$60–$1701–3 hrs
Home › Audi S4
Audi S4 mods
All US Audi S4s. Pick your year, engine and body below to see only what fits your car.
Your S4
Pick your year to see what fits.
This page covers US S4s only. The S5 has its own page.
Engine 2.7T, 4.2L V8 or 3.0T V6
Stock ~250–354 hp
Weight ~3,700–4,000 lb
2000–2025
Power
ECU tune
+30–90whp est. · The biggest gain
Easy$500–$80030–60 min
Power
Cold air intake
+5–15whp est. · More sound
Medium$440–$1,1001–2 hrs
Sound
Cat-back exhaust
+3–10whp est. · Better sound
Medium$1,300–$2,1602–4 hrs
Handling
Coilovers
Adjustable height
Expert$1,200–$2,2005–8 hrs
Handling
Lowering springs
Lower, less roll
Hard$340–$3454–6 hrs
Handling
Rear sway bar
Less understeer
Medium$330–$3601–3 hrs
Brakes
Brake pads
Stronger stops
Medium$80–$2101–2 hrs
Handling
Short shifter
Quicker, tighter shifts
Hard$320–$3402–4 hrs
Handling
Transmission mount
Crisper shifts
Easy$44–$13530–60 min
Power
Supercharger pulley
+30–60whp est. · More boost, needs a tune
Expert$199–$1994–6 hrs
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HP numbers are wheel-horsepower estimates.