After building the Westfield 11, Chris Smith set out to build a copy of the Lotus 7 S3. He apparently did a good job. So good in fact that Caterham, who had purchased the rights to the design from Lotus, sued Westfield for infringing on that design. As part of the settlement, Westfield altered their version and began heading in a different direction (fiberglass tub & bonnet, widebody, IRS, etc.). Those early cars go by the name pre-lit, short for pre-litigation.
-John