Ferrari’s LaFerrari, first unveiled in 2013, stands as one of the marque’s most definitive modern models. As the company’s first full-hybrid hypercar built for public roads, it took numerous prototypes to refine the production version. These test mules were run at Fiorano and beyond between May 2011 and December 2012, before the finished LaFerrari debuted. One of those early cars was recently offered at auction during Monterey Car Week.
Internally designated the “F150 Muletto M4,” this development mule marked the first phase of LaFerrari’s real-world testing. Beneath its bodywork lay the underpinnings of a Ferrari 458 Italia, extensively reworked with an aluminium chassis adapted to house a hybridised F140 V12. That 6.3-litre naturally aspirated engine — first created for the 2003 Enzo and still serving in the modern Purosangue and 12Cilindri — produced 789 hp on its own, forming the backbone of LaFerrari’s eventual 949 hp system output.
Inside, the Prototype M4 retained much of its 458 DNA — black leather seats, tan carpets, and a white-faced tachometer with a 9,000-rpm redline. Yet signs of its experimental role were obvious, from a dashboard toggle switch and high-voltage warning labels to a battery pack mounted in front of the passenger seat and other non-standard fixtures.
Externally, the disguise was even more apparent. Matte black paint, riveted panels, oversized exhausts, and improvised cooling ducts left little doubt about its prototype status. While elements like the mirrors and shields came from the 458, the dramatic intakes and altered proportions hinted at the engineering work underway in Maranello’s development labs.
Sold only to trusted clients with the caveat that they were non-homologated and unsuitable for road or circuit use, these prototypes are extremely rare. At RM Sotheby’s Monterey auction last week, the LaFerrari Prototype M4 fetched US$1,215,000 — a significant figure for a car that represents a pivotal chapter in Ferrari’s move into the hybrid hypercar era.
