Speedwell?
Speedwell:  1. n. Any of various plants of the genus Veronica having clusters of small, usually blue flowers, especially the small, sometimes weedy, herbaceous types. There are about 250 to 300 species of speedwell, most found in the Northern Hemisphere.  2. Former name of the Golders Green telephone exhange in London, England. 3. Trademark of Studio Sprinzel Ltd, (the Sprinzel family's London printing business).  4. Speedwell Performance Conversions: Tuning firm founded in 1957 by John Sprinzel, George Hulbert and Len Adams (see below).  5. Speedwell Blue: Original factory body paint color offered on the Austin-Healey Sprite from its introduction in March 1958 until it was replaced by Iris Blue in January 1959.

 
Founded in 1957 as a part-time venture by John Sprinzel, George Hulbert and Len Adams after Sprinzel won his first race at Goodwood in his Austin A35 which they'd prepared, Speedwell Performance Conversions began offering modified cylinder heads for the BMC A-series engine and suspension modifications for the A35. Future World Driving Champion Graham Hill soon joined the firm, and Speedwell-prepared A35s enjoyed great success in both road racing and rallying, becoming popular for street use as well.

In 1958, the BMC Competitions Department, for whom Sprinzel had begun driving, loaned him a pre-release Sprite in Speedwell Blue, registered PMO200, to be prepared by Speedwell as a private entry on the BMC team in the Alpine rally. This was the Sprite's competition debut and it took the first three places in its class, led by Sprinzel and his navigator, Willy Cave. Speedwell's line expanded to include modifications for Sprites, and their collaborations with designer Frank Costin and the coachworks of Williams & Pritchard produced the "Monza" bonnet, followed by the Speedwell Sprite GT fixed-head coupé and the Speedwell Streamliner, both of which established new speed records in 1960.

Sprinzel left Speedwell in 1960 to head the Speed Equipment Division of the Donald Healey Motor Company, where the Sebring Sprite was homologated and the first examples were produced. For more on the early history of Speedwell, see "The Spritely Years" by John Sprinzel and Tom Coulthard, 1994, Patrick Stephens Limited (ISBN 1 85260 498 0).

Speedwell continued to expand their line to include a very successful electronic rev counter, and speed equipment for other cars like the Mini and the Volkswagon. There is a good article from VolksWorld Magazine by Keith Seume including the later history of Speedwell.
Sebring Sprite?
Sebring Sprite:  1. n.