"Saving Ford's hot hatch from becoming a fridge"
A resource site for owners of the Mk1 & 2 Fiesta

Project Bobcat Ford Fiesta resource site

Ford Gearbox Ratio Guide

When carrying out an engine conversion, it's quite common to want to pick a gearbox that has the most suitable ratios for either quick acceleration or a more comfortable engine rpm for long distance driving. The table below contains the ratios for some popular gearbox choices when converting your retro Ford Fiesta. As with all our guides, the information cannot be guaranteed to be 100% correct and is provided as a guide only. If in doubt please contact a qualified mechanic.

If you can add to the info displayed please email the webmaster at info@projectbobcat.com

Commonly Used Ford Gearboxes

Ford BC Gearbox Ratios

The FWD only Ford BC gearbox was fitted across the Fiesta Mk1 and Mk2 range, it features a 20mm x 17 spline input shaft and requires 2.8 litres of SAE80 grade oil for the 4 speed variant, or 3.1 litres for the 5 speed.

BC Gearboxes were all fitted with a thin aluminium identity tag which is attached via one of the bolt holes on the top side of the box, this tag displays a code which tells you which model, engine type and year your transmission unit comes from. Early boxes (Pre 1986) used a V prefix tag code to signify that the gearbox was a high performance version. The Rs1600i box had a unique bellhousing due to its ignition sensor.

Car Fitted to Year Gear Ratios Identity Tag
1st 2nd 3rd 4th 5th Reverse Final Drive
Mk3 Escort XR3 1981 3.15 1.91 1.28 0.95 0.76 3.84 83WT BB
Mk3 Escort RS1600i 1982-85 3.15 1.91 1.27 0.95 0.83 3.84 H83WT
Mk3 S1 Escort RS Turbo 1985 3.15 1.91 1.27 0.95 0.76 4.27 V85WT
Mk4 Escort XR3i 1.6i 1986 3.15 1.91 1.28 0.95 0.76 4.27 & 4.29 V83WT
Mk4 S2 Escort RS Turbo 1986 3.15 1.91 1.28 0.95 0.76 3.84 86WT BB
Mk2 Fiesta 957cc (4spd) 1983-89 3.58 2.04 1.32 0.95 N/A 3.77 4.06
Mk2 Fiesta 957cc (5spd) 1983-89 3.58 2.04 1.32 0.95 0.76 3.62 4.29
Mk2 Fiesta 1117cc (4spd) 1983-89 3.58 2.04 1.32 0.95 N/A 3.77 3.58
Mk2 Fiesta 1117cc (5spd) 1983-89 3.58 2.04 1.32 0.95 0.76 3.84 & 4.06
Mk2 Fiesta 1.3CVH 1983-86 3.58 2.04 1.35 0.95 0.76 3.84 & 3.82
Mk2 Fiesta 1.4CVH 1986-89 3.58 2.04 1.32 0.95 0.76 3.62 3.84 & 3.82
Mk2 Fiesta 1.6D 1984-89 3.58 1.91 1.28 0.95 0.76 3.62 3.33
Mk2 Fiesta XR2 1.6CVH 1984-86 3.15 1.91 1.28 0.95 0.76 3.62 3.58 V84WT BA
Mk2 Fiesta XR2 1.6CVH 1986-87 3.15 1.91 1.28 0.95 0.76 3.62 3.82 86WT JB0
Mk2 Fiesta XR2 1.6CVH 1987-88 3.15 1.91 1.28 0.95 0.76 3.62 3.82 87WT NA
Mk2 Fiesta XR2 1.6CVH 1988-89 3.15 1.91 1.28 0.95 0.76 3.62 3.82 87WT NB
Mk3 Fiesta 1.0 (4spd) 1989-92 3.58 2.04 1.32 0.95 N/A 4.06
Mk3 Fiesta 1.6S 5 speed 1989-92 3.15 1.91 1.28 0.95 0.76 3.62 3.82
Mk3 Fiesta RS Turbo 1990-92 3.15 1.91 1.28 0.95 0.76 3.82
Mk3 Fiesta RS1800 1992-95 2.86 1.91 1.41 1.10 0.87 3.82
Mk3 Fiesta XR2i 1.6 CVH (EFI) 1989-92 3.15 1.91 1.28 0.95 0.76 4.06
Mk3 Fiesta XR2i 1.8 Zetec (EFI) 1989-92 3.23 2.13 1.48 1.11 0.85 3.82
Mk3 Fiesta 1.8 Diesel (Gearset B) 1989-95 3.58 1.93 1.28 0.95 0.76 3.82

Ford IB5 Gearbox Ratios

The IB5 gearbox was introduced in 1995, it comes in both front and rear starter variations, has a 20mm x 17 spline input shaft and holds 2.8 litres of transmission oil.

Car Fitted to Year Gear Ratios
1st 2nd 3rd 4th 5th Final Drive
Mk4 Fiesta 1.25 Zetec SE 16v 1997-98 3.58 2.04 1.32 0.95 0.76 3.84
Mk4 Fiesta 1.4 Zetec SE 16v 1996-98 3.58 2.04 1.32 0.95 0.76 3.84
Puma 1.7 Zetec SE 16v 1997-02 3.15 1.93 1.41 1.11 0.88 3.82

Ford MTX75 Gearbox Ratios

The MTX75 is a front wheel drive gearbox used in the Ford Mondeo, it weights 36kg and has a length of 39.3 centimetres. Maximum input torque is 280Nm and max input speed is 7000rpm. The recommended transmission oil is ATF+2% Friction modifier, and the box requires 2.61 litres of oil.

Car Fitted to Year Gear Ratios Part Number
1st 2nd 3rd 4th 5th Reverse Final Drive
Mk1 Mondeo 1.6 16V Zetec Hatchback 1992 > 3.42 2.13 1.45 1.03 0.77 3.46 3.82 94ZT-7002-GA
Mk1 Mondeo 1.6 16V Zetec Estate 1992 > 3.42 2.13 1.45 1.03 0.77 3.46 4.06 94ZT-7002-KA
Mk1 Mondeo 1.8 16V Zetec Hatchback 1992 > 3.42 2.13 1.45 1.03 0.77 3.46 4.06 94ZT-7002-KA
Mk1 Mondeo 2.0 16V Zetec Saloon 1992 > 3.23 2.13 1.48 1.11 0.85 3.46 3.82 94ZT-7002-HA
Mk1 Mondeo 2.0 16V Zetec Hatchback 1992 > 3.23 2.13 1.48 1.11 0.85 3.46 4.06 94ZT-7002-EA
Mk1 Mondeo 1.8TD Hatchback 1992 > 3.67 2.05 1.26 0.87 0.67 3.46 4.06 94ZT-7002-DA

Ford MTX75 4x4 Gearbox Ratios

The Mk1 Mondeo 4x4 version of the MTX75 gearbox had the same technical specification as the FWD version, however it required only 2.41 litres of oil, with the transfer case requiring a further 0.68 litres.

Car Fitted to Year Gear Ratios Part Number
1st 2nd 3rd 4th 5th Reverse Final Drive
Mk1 Mondeo 1.8 16V Zetec 4x4 1992 > 3.42 2.13 1.45 1.03 0.77 3.46 4.06 94ZT-7002-BAA
Mk1 Mondeo 2.0 16V Zetec 4x4 1992 > 3.23 2.13 1.48 1.11 0.85 3.46 4.06 94ZT-7002-CAA

The following sources have been used to gather information for this article: Ford Fiesta Workshop Manual 1987, Performance Ford Magazine June 1996, unverified Passionford forum post 2006.

Add a Comment

Page Last Updated: Wednesday 2nd of August 2017

Facebook

Google Plus