Care of the June 1959 edition of Sporting Motorist (Sport, Tuning, Driving and Touring) is this drivers review of the Yimkin Sprite by F1 racing driver 'Jack Fairman'. He later went on to be Technical Director of Gordon and Glyn (Motor Sales) who also owned Yimkin Engineering LTD (Stage tuning, FJ and Sports Racing Cars). Both of which were owned by Phyllis Hebert.
On a drive to Silverstone the 'Yimkin Sprite' is described as 'extremely lively and difficult to appreciate that such performance could come from the same unit that propels the Morris Minor and Austin saloons'. Full marks are also awarded to the team for ' ... a comparatively small outlay here is a car which goes, steers, stops, and corners, all in remarkable safety. Far better for the enthusiastic chap than spending the same amount on some doubtful heap or hybrid that is a short cut to the mortuary.
True speeds (not speedo readings) are recorded:
0 to 50 m.p.h. 13· 1 secs
0 to 60 m.p.h. 18·25 secs
There is a link to download the article here.