Any of the high end units are more than adequate in a 2,400 lb. Cobra and the reaction is very predictable. Allthough there very noisy,but thats why you drive a cobra. Auburns are pretty hot here in these parts, Mustang boys love em! High Bob. I ran a Detroit in my Camaro before I went to a spool, it was great for the street, Allthough a rebuilt posi works well for a couple a years till it needs a rebuild.400-500 burnouts.Cheap to rebuild if you have done it before.I personally would'nt run a open, there useless and not meant for a performance machine. Spools aren't for the street allthough some clowns run them,they must like the sound of the tires scratching and jumping when making a two-mile an hour turn.