The BMW M3 E46 may be 16 years old, but it’s considered one of the Bavarian car maker’s finest moments, combining the M-division’s qualities into a balanced, no nonsense package. And then there’s this particular unit.

Somewhere along the road, the owner of this 2004 E46 M3 decided he didn’t want BMW’s carefully crafted recipe of a high-performance sports car and reckoned it could have a bit more bite. A bit more of everything, that is.

That’s why this car comes with the monstrous, odd firing S85 under the hood. For those not familiar with BMW’s internal nomenclature, that’s the 507hp and 520 Nm (384 lb-ft) of torque, 5.0-litre V10 that came with the previous-gen M5/M6.

According to the vehicle’s owner the swap was made by himself, and the gearbox coping with the new powerplant’s grunt is a six-speed manual taken from a E92 M3 V8. This M3 could be considered Doctor Frankenstein’s doing, but it features all the creature comforts, including heated nappa black leather interior.

The car is currently offered for sale on eBay for £30,000 ($44,473), mainly due to the owner’s desire to “get another E30 M3” (and do God knows with it), as he points out.

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