Contributed by: F. Navest
During the design stage of the MGB a choice was made to have a 4-speed transmission, or alternatively a 4-speed transmission complemented by an overdrive. The overdrive, a fifth gear, was realised by adding a housing with planetary gears to a modified basic gearbox. The overdrive transmission would reduce the engine speed by approximately 8 per cent. This special option was to save fuel and reduce noise emission. It does save fuel.
Upon working out the mechanical details of these two setups it became evident that mechanically it was not possible to have the gear lever for both transmissions in exactly same position. Due to this complication the hole for the gearlever in the car body was chosen to be oblong. The gear lever of the standard 4-speed transmission would pass through the body further forward from the driver than the lever working the overdrive transmission.
For driver’s ergonomic comfort the position of the gearlever knob was chosen to be best where the knob of a lever that passes through the rear part of the oblong hole, close to the driver.
In order to meet this requirement the position of the standard transmission lever knob had to be in same position as the one of the overdrive transmission.
This the reason why a Mk I MGB is fitted with a lever that is bent in the typical way only intended for a MGB with standard transmission. The lever is bent towards the driver.
Cars fitted with an overdrive transmission have their lever passing through the oblong hole towards the rear. This particular lever is straight as the lever knob is in the correct position. This lever is simply straight instead of bent.
Apart from this apparent difference, these two gear levers also differ in length by which they stick into the gear selection mechanism.
By using a bent lever in overdrive transmission you run the risk of developing problems switching gears.