I don't know exactly what the internal proceedures in Morgan are for this but I will make some guesses.

The car, at least on paper, is a Morgan Plus 4, it is then transfered to Aero Racing who fit the more powerful engine. So, in effect, the more powerful engine is an aftermarket fitting.

What you may be able to get from Morgan's homologation engineer is a letter which states that there is no technical reason against the fitting of a more powerful engine such as the Cosworth model number xxx to car VIN xxxxx.

Does the ARP4 have full OBD2 diagnostics? This may be an important requirement in some countries, Germany for example.

Peter

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