Metering Unit PI KMI Reconditioned Exchange RKC0220R 1973 onward 125 BHP PI & TR6 CR -Use with 311399 18/58 Camshaft.
Built to order allow 2- 4 weeks
If the rotor is siezed, there will be a surcharge of £140 to cover a new rotor
This unit is supposed to be installed 20-45 degrees ATDC, vs TDC for all other units.
I think the reason for was this was to eliminate fuel being injected during the 36 degree valve overlap period, eg the exhaust valves closes 18 degrees after top dead centre, or 2 degrees sooner (16 degrees ATDC) if the cam is installed 2 degrees advanced. This would prevent un burnt fuel entering the exhaust. Afterall this was an 'Emission Control Unit'. Setting to early timing will not harm performance.
If you want to install for emission control, with the rocker cover removed ensure the exhaust valve on No 1 Cylinder has just closed, whilst the injector port for no 1 cylinder is just starting to open.