I've got a bookmark on my computer at home to a website with free hi res .eps images of various logos, including the Crossfire lettering. It isn't a font per se, but rather a vector graphic of the lettering found on the back of the car. This should suit your purpose for sign or banner making as vector graphics can be scaled infinitely without becoming pixelated.

I'll post a link later tonight when I get home. After I walk the dog. And have dinner.

Hey, I've got priorities ya know!!!!