What do you have to chase in your neck of the woods? I chased jacks and foxes until I moved east into non-sighthound country. Teach the retired racer to come when called, every time, and then take them, the two dogs, out and let them nose around. If the instinct is their, which it will be for the racer, they will chase what they see. Remember, these dogs hunt by sight so they have to be able to see at their level. You need open country without fences. I loved it. I did teach a whippet to fluch pheasants after I had hunted him for rabbits. Shot enough to keep things interesting. He also retrieved very well. The rabbits and jacks got him hunting the birds were just icing.
Dr Fatguy