Mercedes-AMG C63 W205 or Audi RS6 C8? They're rivals, so owners often weigh one against the other. Here's how far each one goes, using the makers' and tuners' own figures from our two guides.
At a glance
| Mercedes-AMG C63 W205 | Audi RS6 C8 | |
|---|---|---|
| Years | 2015–2021 (coupé and cabriolet later) | 2020– |
| Engine | 4.0 twin-turbo V8 M177 | 4.0 TFSI twin-turbo V8 (EA825) |
| Stock power | 476 PS (C63) / 510 PS (C63 S) | 591 hp / 590 lb-ft (US) |
Power by stage
| Mercedes-AMG C63 W205 | Audi RS6 C8 | |
|---|---|---|
| Stock | 476–510 PS | 591 hp |
| Stage 1 | 550–611 hp | 668–753 hp |
| Stage 2 | 590–667 hp | 720–819 hp |
| Stage 3 | 700–820 hp | 760–950+ hp |
| Stage 4 | 830–950 hp | 1,000+ hp |
Figures are the tuners' own claims from each guide, on the fuel each tuner states.
Typical parts cost
| Mercedes-AMG C63 W205 | Audi RS6 C8 | |
|---|---|---|
| Stage 1 | remaps €990 (BR-Performance), £720–£1,440 (Litchfield) or $1,999–$3,280 (Weistec, RENNtech); CPC upgrade for 2019-on cars $1,699 (Weistec); plug-in modules $767 (RaceChip) or €3,799 (DTE). | 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. |
| Stage 2 | downpipes $3,079 (Weistec) or £2,180.34–£5,746.14 (Milltek, track-only or with sports cats); CSF heat exchanger $749; Weistec airboxes $1,499; RENNtech R1 package $6,880. | software $1,195 (CarBahn) or $3,049 (MTM); Litchfield with an exhaust £5,905–£9,782 before VAT. |
| Stage 3 | turbos €2,940.33 before VAT (TTE760+), $2,995 send-in (Pure900) or $5,499 (Weistec W.3); RENNtech turbo packages $13,840–$23,880; fuel pumps $4,280 (RENNtech). | IE software for Pure900 turbos $2,299; the turbos are extra. |
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 Mercedes-AMG C63 W205 reaches 830–950 hp and the Audi RS6 C8 1,000+ hp.