Are you looking for Touring or Super Touring?
Engine is too big for STU, so that's out. You could make it a T3 or T4 car, depending on weight and whatnot. You would need to submit a request to have the car classed. go to http://crbscca.com/
and fill out the form requesting classification. Put as much info as you can in the form so they have the best ability to place the request. It'll get sent to the proper committee and you should have an answer shortly before parts for the car become obsolete.