Now Ford has reacted to the demand by offering an upgrade to the 305PS RS hatch to increase performance by an extra 45PS in the form of an MP350 upgrade pack.
The MP350 performance kit upgrade will not include the RS 500 badges displayed on the matt black limited edition, but the upgrade includes an air filter box, larger exhaust downpipe and higher-capacity fuel pump.
Only 101 Ford Focus RS 500 models were sold in the UK out of the 500 cars produced, and demand for the powerful hot hatch meant many customers missed out.
Ford claims it could have sold five times as many Ford Focus RS 500 units in the UK after 101 were sold within seven days.
Mark Simpson, Ford Britain marketing director, said: "Focus RS500 has raised the Ford performance bar in every way – it’s the fastest-selling model in Ford’s UK history, with five times more customers than we had cars for."
"The MP350 kit has been developed to meet some of this additional demand and allow enthusiasts with cars in standard tune to enjoy even greater performance."
The Ford Focus RS 500 cost £35,450 each, but the upgrade for the RS will cost £1,995. The upgrade will not endanger the warranty, said Simpson.