No problem:

YBB = Fitted to the original 3 door Sierra AND Saphire (2WD) models.

YBD = RS500......these were YBB units that Cosworth converted for homologation.

YBJ/YBG = As fitted to 4 x 4 Saphire (YBJ is the Euro spec emmision trim version and the YBG was produced for the USA more restrictive emission standards).

YBT = Fitted to Escort Cosworths, known as the "Large Turbo" model (Garrett T34 turbo)

YBP = Fitted to Escort Cosworth "Small Turbo" model (Garrett T25 ne T28).

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