The air-dam, showing how it scoops air into the slot for the oil cooler and lower half of the radiator and will do so even when the bumper and hanging number plate is fitted: (MG-Cars.org.uk)
Raised number-plate opens up the slots in the standard apron: (V8 Register)
Duct BHH1614 directs air through the under-slung oil cooler and back to the lower part of the V8 and 77 and later 4-cylinder radiators, which extend below the chassis rails. This original flat fibre-board had taken up a curved shape allowing a lot of air to bypass the cooler and radiator, I added the metal strip to force it into the correct rectangular shape:
Current stock is pre-formed plastic which should hold its shape better: (Moss Europe)
Duct BHH1622 (moulded plastic) on pre-77 4-cylinder rubber-bumper cars, directing the air-flow up to the radiator which doesn't extend below the chassis rails: (MGB Tips)
77 and later used a deeper radiator like the V8 and so used the V8 duct, as well as this mud/acoustic shield BHH2127 behind the radiator sitting on top of the chassis rails. The bottom hose passes through the shield at the top of the picture: (MGB Experience)
