The Griffith 200 and 400-series cars were basically the result of Jack Griffith getting bored one day.
He had, in his shop, two things:
1: A wrecked Shelby Cobra; body was trashed but the engine and tranny were in good shape.
2: A TVR Grantura with a blown engine.
He noticed that the 289 smallblock V-8 from the Cobra would just barely fit into the Grantura's engine bay, and the transmission would fit as well, so he dropped them in. After rebuilding the suspension and lengthening the TVR's frame about 8 inches, he had the first of the Griffith 200's.
This was a car with better aerodynamics than the Cobra, with the same engine and tranny, that weighed over 600lbs less than the Shelby and had a much shorter wheelbase. The top-end on the thing was well over 160, and it did 0-100Kph in less than 4 seconds. Bear in mind, this was in the mid-70's. The only problem was that the short wheelbase, while making the car very quick-handling and manuverable, also made it prone to fishtailing in turns, especially since it was so overpowered.
For more info, just google "Griffith 400" or "Griffith 200." Every now and again, one comes up for sale on Ebay. If you can find a copy, Mike Mooney's book
The Griffith Years is the best source on these things.
http://www.griffithyears.com/