M type have a 4 cylinder overhead camshaft engine with a capacity of 847cc. It went into production in 1929 having been introduced to the public at the 1928 London Motor Show. The car is based largely on the Morris Minor, sharing the same chassis layout, engine and running gear. Top speed is about impressive 65 mph.
Brooklands race result was an unqualified success for the little 12/12 M type, finishing 3rd, 4th, 5th, 6th and 7th in their class behind two Riley Nines, and 14th, 17th, 18th, 19th and 20th overall, as well as carrying off the overall Team Prize. The fastest M type covered 1,445.63 miles in the 24 hours and the slowest 1,385.31 miles giving an average speed for all the cars between 60.23 and 57.72mph. The MG factory, incorporated the new valve timing into the production cars and marketed a ‘Double Twelve M Type’ which is a replica of the successful Brooklands cars. The 12/12 Replicas were built between August and December 1930 and cost their owners £245, which was a considerable increase over the £185 of a standard M type.
MG 18/80 have an 80-bhp 2468-cc (69 x 110 mm) six-cylinder OHC engine with twin SU carburettors. It was designed entirely by MG, rather than based on a modified Morris chassis like the Company's smaller models. Mk I models (from late 1928) had a three-speed gearbox, Mk II models (from 1929) have a four-speed gearbox, improved brakes, sturdier chassis, etc.