It sounds like your car would be a perfect fit for the CTCRC Thunder Saloons Championship, and id need confirmation, but im sure it sounds like it might go into the BOSS (Blue Oval Saloon) championship, where there are plenty of other Fords and particularly Sapphire Sierra's to dice with!
Infact, Im pretty sure Ash in his Sierra XR4 is running the 2.9 V6 cossy in the BOSS championship, and that goes well!
The regs are up on the website : http://classictouringcars.com/champ_thunder.html
, but if you want more info you can email Andy Johnson at:
and he will have all the answers!
Be good to see you out racing