BMW’s M division spent two years building the S54 from scratch, and the result was a naturally aspirated straight-six that revved to 8,000 RPM and made 343 horsepower from just 3.2 liters. Each cylinder got its own throttle body, and at launch it was BMW’s highest-output naturally aspirated engine per liter, McLaren F1 aside. The E46 M3 was the last pure M car, and no turbo or trick was needed. Toyota rated the A80 Supra Turbo at 320 horsepower and quietly built the 2JZ-GTE to handle far more. Its twin turbos ran in sequence, one working at low RPM and the second joining around 4,000 for full boost, and tuners pushed it past 1,000 horsepower on a stock engine block with no internal modifications. Toyota lied about what was under the hood — in the best way possible.