Background
Announced in 1958, the MG A Twin-cam was intended to capitalise on the success of the 1500, with which it shared an almost-identical external appearance, with the only visual differences being the disc wheels and subtle twin-cam badging on the bonnet and boot lid.
Underneath, however, this was an entirely new vehicle. The standard single-cam 1500 engine made way for a DOHC unit also of 1.5-litre displacement, producing 108bhp and 104 lb/ft of torque at its peak, propelling the Twin-Cam to a top speed of 113 mph and giving it a 0-62 time of 9.1 seconds, which was outstanding in its day.
The block itself was an experimental engine developed from the standard B-series block, and was the first overhead-cam engine MG had used since the PB in the 1930s. Designed with competition purposes in mind to boost the image of MG as a competitive manufacturer, the twin-cam engine employed incredibly high compression (9.9:1) which necessitated the use of high-grade fuel and perfect ignition timing.
Unfortunately, however, these two things were hard to come by, and as a result of this and its complex nature, the twin-cam engine developed a reputation for unreliability, with excessive oil consumption (partly as a result of the chromed rings) and a habit of burning through its pistons.
Eventually, these issues were addressed by engineers working with Nuffield Exports ltd, though this was only addressed towards the very end of the production run, making late cars all the more desirable.







