I think you are talking of this engine


I used to run one, and was not impressed by the ignition. In the pictures at rcshowcase.com I also see the "fix" with the hose clamp.

I have no data on the ignition, other than that it uses a steel proximity sensor (not a hall sensor) to fire.
The engine is no longer on rcshowcase's website, but they may be able to help you out.