The M8 Coupe ended production in 2025. The rest of the 8 Series follows after the 2026 model year. While BMW has not announced a direct successor to its grand tourer, German tuner G-Power has quietly reframed the M850i — the variant still available from remaining inventory — with a software package that costs less than €2,500 and outguns the standard M8 on peak output without touching a single body panel.
The Numbers That Matter
G-Power’s GP-620 package extracts roughly 90 additional horsepower from BMW’s 4.4-liter twin-turbo V8, pushing the M850i past the standard M8’s factory output on paper.
The stock M850i produces 523 hp and 553 lb-ft (750 Nm). G-Power’s GP-620 software raises those figures to approximately 612 mechanical horsepower and 627 lb-ft (850 Nm), according to AutoEvolution’s reporting on G-Power’s claimed figures. For context, 612 mechanical horsepower is the U.S.-unit equivalent of G-Power’s stated 620 metric horsepower (PS). That clears the standard M8’s 600 PS — but one ceiling it does not clear is the M8 Competition, which sits at 625 PS. Worth knowing before the bragging starts.
The performance package breaks down cleanly, per Autoblog and AutoEvolution‘s reporting:
- GP-620 software: €2,495 (~$2,770)
- Speed limiter raised to 186 mph: +€495
- Upgraded air filter: +€238
- Digital cluster displaying to 205 mph: +€395
- Full performance bundle combined: ~€3,623 (~$4,000+)
The Sleeper Case
The most compelling configuration keeps every factory badge intact and delivers higher quoted output than the standard M8 for the price of a long-haul flight.
That is the core proposition. The software alone — or software paired with the limiter, filter, and cluster bundle — is where the value lives. The car carries the same badges, the same ride height, and not a gram of aftermarket carbon fiber. It is not a statement build; it is an advantage that is invisible from the outside. G-Power’s power figures are manufacturer-claimed and have not been independently dyno-verified, so treat the output numbers as reported rather than confirmed. It is also worth noting that a software tune of this nature may affect factory warranty coverage, emissions compliance, and long-term drivetrain durability — factors worth discussing with a specialist before committing.
G-Power’s wider catalog goes considerably further: sport exhaust, downpipes, carbon-fiber hood, wing, illuminated steering wheel, and 21-inch Hurricane RS wheels. The complete build hits €36,231, or roughly $40,210, according to Autoblog. That is where a focused software story becomes a full styling project. According to AutoEvolution’s reporting, the tuned M850i reaches a claimed top speed of 186 mph with the limiter removed — an option that costs an additional €495 and is arguably the second-best value in the entire catalog.
Last Call for the 8 Series
BMW is closing the book on the 8 Series, and G-Power has written a compelling final footnote for buyers still in the window.
The M8 Coupe ended production in 2025. The broader 8 Series lineup concludes after the 2026 model year, per CarBuzz, with buyers limited to existing inventory rather than new orders. BMW has not announced a direct replacement. For those still considering a purchase in this window, the GP-620 package offers a distinctive closing argument: on quoted peak output alone, the M850i does not merely close the gap with the standard M8 — it steps over it.
