Audi RS6 C8 or Ford Mustang GT S550? Both reach the 1,000 hp class when fully built. Here's how far each one goes, using the makers' and tuners' own figures from our two guides.
At a glance
| Audi RS6 C8 | Ford Mustang GT S550 | |
|---|---|---|
| Years | 2020– | 2015–2023 |
| Engine | 4.0 TFSI twin-turbo V8 (EA825) | 5.0 Coyote V8 (Gen 2 / Gen 3) |
| Stock power | 591 hp / 590 lb-ft (US) | 460 hp / 420 lb-ft (US, 2018–21) |
Power by stage
| Audi RS6 C8 | Ford Mustang GT S550 | |
|---|---|---|
| Stock | 591 hp | 460 hp |
| Stage 1 | 668–753 hp | ≈479 hp |
| Stage 2 | 720–819 hp | ≈490–510 hp |
| Stage 3 | 760–950+ hp | 623–825 hp |
| Stage 4 | 1,000+ hp | 1,000+ hp |
Figures are the tuners' own claims from each guide, on the fuel each tuner states.
Typical parts cost
| Audi RS6 C8 | Ford Mustang GT S550 | |
|---|---|---|
| Stage 1 | software $950–$2,599 (034, IE, APR, MTM), or $1,500 for 034's engine and gearbox bundle; Litchfield £1,800 including VAT. Unitronic sells through dealers only. | Lund custom tune from $325 (tuner device extra); Ford Performance calibration with intake and throttle body $1,535. |
| Stage 2 | software $1,195 (CarBahn) or $3,049 (MTM); Litchfield with an exhaust £5,905–£9,782 before VAT. | BBK long-tube headers $850. |
| Stage 3 | IE software for Pure900 turbos $2,299; the turbos are extra. | supercharger kits $6,950–$9,596 (Ford Performance, Whipple, ProCharger, Roush, Edelbrock); Tremec Magnum XL swap $6,200. |
List prices from the guides, before shipping, import tax and fitting. "—" means that guide has no cost line for the stage.
Where each one ends up
At Stage 4 the Audi RS6 C8 reaches 1,000+ hp and the Ford Mustang GT S550 1,000+ hp.