Ratios Final Drives Which Ratio ? There are a number of ways to determine which ratio your gearbox uses. The table below is a good indication, but is by no means exhaustive. Many standard Hewland ratios are used in customer specific gearboxes, and occasionally special ratios are made specifically for customers. Most modern Hewland ratios have the gear family etched onto at least one of the pair of gears that comprise a ratio, and in all instances the gear family will be shown on the cardboard carton that the ratios are shipped in. Standard Hewland Gearboxes Gearbox Gear Family   Gearbox GearFamily DG DG   MK? (HC?) MK 5 or Mk8 DGB DGN   MVE-STA MVE DGC DGN   NLT DGN FG FT   NMT 104 FGA FT   NST MK5 FGB FT   PCT HP FGC FT   SGT TPT FT FT   SL LSG FTR FTR   STA MVE HP HP   TE 104 IGTC DGN   TGTA DGN LD LD   TLS TLS LSG LSG   VG/VGC VG and VGC only made to special order, contact SALES dept for details. Customer Special Gearboxes Over the years, racing car constructors have produced their own gearboxes, which utilise standard Hewland gear ratios. Below is a list of some of these, with the Hewland gear ratios that they used. Dallara F3 cars, 1987 to 2001. Mk 5 Reynard F3 cars, all. Mk 5 Formula Vauxhall cars, 1998+ Mk 5 Reynard F3000 cars, 1988 to 1992 FT Lola F3000 cars, 1986 to 1992 FT Lola F3000 cars, 1993 to 2001 TPT