Johannesburg - The contraction 'Hemi' when applied to internal combustion engines indicates a hemispherical combustion chamber, with the valve stems at an angle to each other.
In the days before multivalve cylinder heads, it had the double advantage that the valves could be made much larger than those of a conventional 'flathead' engine, and the inlet and exhaust ports were much straighter, leading to better gas flow at high revs.
The principle goes back to 1901, but the biggest proponent of this rugged, high-torque architecture has always been Chrysler - so much so that it has actually trademarked the word Hemi as a brand name for the muscular big-bore V8s produced by its SRT performance division.
These were always naturally aspirated, until the advent in 2014 of the supercharged 6.2-litre Hellcat engine, rated at a fire-breathing 520kW and 883Nm - but it's only available in the two-door Charger and four-door Challenger models, neither of which is made in right-hand drive, so we can't get them here.
The hottest hemi you can buy in South Africa is the 6.4-litre naturally-aspirated V8 in the SRT8 derivatives of the Chrysler 300C and Jeep Grand Cherokee, good for a respectable 347kW and 631Nm - but it's not in the same league as the Hellcat.