1954 Austin A30 differential swap from 4.55 to 4.22 

This weekend Bertie the A30 is getting a long overdue final drive ratio change from 9/41 (4.55: 1) to a later standard Morris Minor 9/38 (4.22 : 1)that will better suit the added power and torque of the BMC Gold Seal 1098cc engine that has been fitted at some time in the past. The increase in speed or drop in engine revs will not be dramatic being just a litte under 7.5%. Bought the 4.22 diff off ebay recently for £100 incl postage. Its innards look superficially ok without but as second hand unwarranted and untested one takes a gamble that it will not howl in use. Secondhand gearboxes are the same. Just won a spare smooth case remote change with compatible innards to swap over to the A30 direct change case, if need arises, for just £25. Looked really clean and good but only time will tell. Most of these gambles pay off just like the car itself for £1400 on the hammer at ACA auction 6 April 2024. A drive vid of this diff should follow soon. If it is unacceptably noisy it will be a case of finding and fitting another.