Perhaps responding to purists’ complaints, particularly in the U.S., the 1973 MGB regained a traditional flush grille, though now it was plastic with a cross-hatched design and a central shield badge. The recessed grille with its chrome surround, inner rings and floating octagon MG badge was discontinued. Wipers were now matte black instead of chrome and a tonneau was standard equipment.
The other big news for the 1973 MGB was the fitment of the alloy Buick-Rover 3.5-liter V8 engine into the GT. The lightweight V8 weighed little more than the MGB’s 4-cylinder and significantly less than the MGC’s 600-plus pound six-cylinder unit. Ken Costello had been fitting V8s into MGBs in the UK since 1970 and the factory improved on his installation, re-routing the manifolds so that the standard hood could be used. Even with the compression ratio reduced to 8.25:1, performance was sparkling with 0-60 in around eight seconds and a top speed of 125 mph.
Nine LHD GT V8s (some sources say seven) were sent to the U.S., which seemed like the obvious market. However, U.S. emissions were increasingly strict and the Arab oil embargo took place, so the outlook was unfavorable. In addition, British Leyland was miserly in allotting the V8 engines to MG, so total production amounted to a mere 2591 units between 1972-1977. Only 1856 chrome bumper GTs were built, followed by 735 rubber bumper cars.
MGB sales continued at the previous year’s pace, with 21,801 1973 roadsters sold worldwide, 17,403 of which came to the U.S. Only 3178 convertibles were sold in the UK. In addition, 820 RHD and LHD cars were exported elsewhere. A total of 11,550 1973 MGB GTs found buyers, and again unusually, the UK took the majority with 6563 against 3747 coming to the U.S.
Some unusual colors were added to the palette for 1973, along with a new (and quite unusual) interior ginger color called Ochre which only lasted for a year. Special order Black cars could have Navy or Ochre interiors. Other paint colors on offer included Teal Blue, Harvest Gold, Limeflower Green, Green Mallard, Blaze Orange, Balck Tulip Purple, Damask Red, Bronze Yellow and Glacier White. Teal Blue, Green Mallard and Black Tulip had Ochre interiors, the rest were Navy Blue. Autumn Leaf returned for late series cars in Teal Blue, Green Mallard and Black Tulip. Late model Glacier White cars often had Black trim. Flame Red and Aqua Turquoise were discontinued at the end of 1972.