Not sure if it would qualify as the "most valuable", but the "Megabuck" Pantera from the 80's certainly set a new standard for unlimited spending ... from the twin turbo 427 SOHC engine, McLaren uprights, inconel exhaust, Hewland gearbox, airjacks, completely re-engineered suspension and engine compartment, etc., etc.
The actual $ spent on this Pantera (reportedly millions) is the stuff of legends!
I saw the car at the Newporter concours in the mid 80's. The development goals were so ambitious that it still wasn't "finished" at that time.
Dave
PANTERA INTERNATIONAL
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