The FROG .049 achieved what may well have been one of the objectives set by the IMA Board of Directors - it was the first of the British .049 glow-plug motors to put in an appearance on the domestic market. The engine was in production by May 1959 being formally announced in July 1959 as reflected in the advertisement which is reproduced here. It thus beat the rival D-C Bantam and A-M .049 into the marketplace by at least four months and the Cobra .049 by well over a year. The initial selling price was set at 2 9s 6d (2.48) slightly higher than the FROG 80 diesel which continued in production.

For better or worse IMA had decided that the line of least resistance towards the development of their own .049 cuin. glow-plug model lay in simply converting their existing and well-proven 80 diesel model to glow-plug ignition. However it is to the credit of IMAs chief engine designer George Fletcher that he seems to have realized that a direct conversion might not yield the best results.

Accordingly while IMA management evidently directed Fletcher to control costs by maximizing the use of components of the 80 diesel which were already in IMAs production program Fletcher was given sufficient leeway to permit experimenting with changes in the cylinder arrangements to maximize the engines potential in glow-plug form.