An article submitted by David Else

This article was originally published in 1975. We would like to obtain a copy of the original text and photographs if at all possible.
The article is stored in 4 large .pdf files.

Re-building an HP20 Engine - Part 1

Re-building an HP20 Engine - Part 2

Re-building an HP20 Engine - Part 3

Re-building an HP20 Engine - Part 4