Mercedes might have been forced to pull most of its V8 models from America this year, but 15 years ago it was difficult to think of a Benz that hadn’t been stuffed full of V8.

Following its 1999 takeover by, and integration with, Mercedes, AMG was on a roll, and the combination of those three letters and eight cylinders created some seriously exciting, and occasionally bizarre, combinations.

Take the R63, for example. The regular non-AMG R-Class was already a pretty strange beast, not seeming to know whether it was a minivan or an SUV. Mercedes called the R-Class a “sports tourer” but if it had just fitted a less sloping front end the car would probably have been accepted as a sportier SUV before the idea had come fashionable.

Depending on market, they came with a choice of V6 petrol or diesel engines, or a naturally aspirated V8 in the first couple of years from the 2005 launch. All built at Daimler’s Vance plant in Alabama (until a 2015 switch to Indiana), all fairly sensible, and the ideal car for a rich soccer mom with a taste for the three-pointed star.

Related: Did Mercedes Suspend V8 Sales Over “Quality Issues” Not Supply Problems?

But there wasn’t much sensible about the R63 that rocked up for 2007. AMG had mostly switched from the old supercharged 5.4-liter (but badged 5.5) V8 to its new naturally aspirated 6.2-liter (but badged 6.3) V8 at this point, but it kept the Kompressor motor alive for the AMG-fettled G Wagen where the blown motor’s torquier nature made more sense. It probably would have made more sense in the R-class too given its people moving focus and gargantuan 5236 lb (2375kg) heft, but instead of an R55 we got an R63.

The natty 6.2 might have needed more revs to get moving, but it ultimately made more power (503 hp vs 469 hp) and still sent the R63 down the road at a fair old clip. Hooked up to Merc’s 7G-Tronic automatic and 4Matic all-wheel drive system, the jumbo AMG could hit 62 mph in 5.1 seconds, and would nudge 185 mph (297 km/h) if you asked for the 155 mph (250 km/h) limiter to be removed.

But the AMG oddball struggled to find buyers and was canned after just one year on sale. It’s estimated that only 200 were built, making this one of the rarest AMGs of all, including specials like the Black Series version of the SL, SLS and CLK.

Prices, however, are somewhat lower. We found a silver R63 on Auto Trader for $35,000 in California, which gives a rough idea of what you might expect to pay for this 2007 example currently being offered on Bring-a-Trailer. It’s done 131,000 miles, but a replacement cam and lifters removes one of the worries with these engines, and the leather interior looks to have lasted well.

If you like the idea of this AMG sleeper get your bids in before the auction ends this Thursday.