Munchen Fan said:The worst, and I say this from personal experience, was the BMC 6 cylinder used in the MGC. Took me 5 years to determine the cause of overheating-studs that would stretch in length as the engine warmed, allowing coolant into the combustion chamber.
The design of the new straight 6 to power the MGC and Austin 3000 saloon was started by BMC but the engine was basically dumped when the merger with Leyland came a year and a bit later - they weren't interested in developing Austin's engines (they had their own duds to try and make reliable like the Triumph Stag quirky and unreliable V8, when they should have used the BOP derived and reliable Rover V8).
The MGC engine came in low on power and overweight and no money was ever allocated to fix that - it was never going to be a brilliant straight 6 but could have been much better than it was.
I added 40 bhp, lowered fuel consumption and increased performance drastically on my MGC by designing and building a triple carb set up, each with a straight shot at the intake ports instead of the circuitous factory twin SU set up (see below), some head work, a mild cam change and a tube header - it transformed the car and made the lost opportunity BMC had even more unfortunate.
Stock:
My version:
Some handling fixes to correct flaws in the stock set up made the car handle far better than any MGC as it came of the production line. Another missed opportunity by BLMC.