iirc
Cosworth intended to price the DFV at £9000 (for general sale after the Lotus-exclusive 1967 season)
(but Ford told Cosworth 'charge more - we will make sure the right teams can buy them')
Ford UK paid only £100000 to make the FVA & DFV prototypes exist
similarly (it's said) Repco had a £10000/$20000 budget for their project - the engine that won the 1966 WDC & WCC
the 1100cc JAP engine used in the F3-style Cooper was the cheapest ever used in a WC F1 race - Schell 1950 Monaco GP
the 1100cc car's dry weight was c.250 kg (and the 500 cc JAP race engine cost £88)
some say he used the car 500cc-engined in that race - btw min weight was 440 lb for UK F500 (also then international F3 ?)
