This car is never been a ford cosworth just a ford rs(rallysport)
All of the real ford cosworth roadcars where ford cosworth and the rs2000 is badged rs not cosworth.
And the stock escort rs 2000 is good for 150 hp and i believe they had fwd and 4x4 versions of the car but it's was never fitted from the factory with the famous yb cosworth the one that you talk about.
The owner made a mistake thay say it's group b rally car but it's closer to f2 class ford ford rs2000 maxi evo 2 rallycar
Here is example of such a car

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