The 2016 Cadillac CTS-V is already one of the most powerful four-doors on the planet, but could an even hotter version be in the works?

The current car develops a massive 640 horsepower and 630 pound-feet of torque from its supercharged 6.2-liter LT4 V-8, the same V-8 found in the Corvette Z06, but a well-placed source at Cadillac has revealed to Automobile that this isn’t the limit.

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“I don’t know where it stops, but it’s not at 640 hp, that’s for sure,” the source said.

It’s thought Cadillac’s smaller ATS-V will eventually get a hotter ‘Plus’ model to do battle with the likes of the latest BMW M4 GTS and a planned Mercedes-AMG C63 Black Series, so it’s conceivable Cadillac may be planning something similar for the CTS-V.

How much extra power may a potential CTS-V Plus model pack? It will likely depend on what’s in store for new versions of the BMW M5 and Mercedes-AMG E63 due on the market in the next 12-24 months.

Stay tuned for an update.

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