Resale values for the near-legendary E39 M5 are getting hitting the elbow curve in a big way. BMW’s turn-of-the-century executive express was a performance steal just three or four years ago, but with well-kept, low mileage examples disappearing, alternatives like the 540i M-sport are getting attention. Think of this car as a 562i M Super Sport.

If it’s a bargain M5 you’re seeking, this project 528i checks all the boxes. V8 power and then some comes from a boosted LS1 complete with forged internals and connected to the rear wheels through a transplanted and beefed-up 6-speed Tremec manual. It might not have the M5 pedigree, but who needs it with twice the horsepower.

American Bahnstormer

Make that more than twice. An M5 was powerful when this car was built, but this produces a supercars-only 801 horses at the rear wheels. That means it’s making somewhere in the vicinity of 930 horses at the crank. Taking a look at the build sheet for this monster motor, you’d be forgiven for thinking it was Richard Rawling’s Christmas list. And the VANOS will never fail.

The car is currently listed on Bringatrailer at under $20,000, so what’s the catch? If you’re looking for a pristine interior and flawless cosmetics, there might be a few nits to pick here. The description mentions a few tired seams, pixels are failing in the odometer which reads around 100k, and the clean black paint is said to display a few of the typical blemishes you’d expect from an 18-year old car.

However, that’s not to say the vehicle is poorly kept. Inside it features 18-way power seats borrowed from a 7-series, a 7-inch touchscreen Android head unit, and multiple engine-management accessories including a methanol injection controller.

Could you endure an airbag light and a few missing pixels for the sleeper to end all sleepers? You’ve got 24 hours to decide.