I thought I would do a little blog post about the latest
work that has been done on the Hopper special’s Lea Francis engine.
It is not often when you get original correspondence from
the engine builder about how he built his engine. In this case we were very lucky
when it came to the Hopper special valves.
Below is a picture of a standard Lea Francis valve which is
suitable for the 1500cc Dirt Track engine.
Std Lea Francis valve |
The next couple of photos show a letter and drawing from Ian
Hopper about how he wanted to modify the valves for the Hopper special.
Letter from Ian Hopper |
Drawing showing modifications to the inlet valve |
Given Ian wanted to build his engine this way, it was only
right to remove all the valves and machine them as he intended. The photo below
shows the newly machined valves to Hopper specification as well as some of Ian’s
old valves.
New valves modified to Hopper's specification along with some of the original valves |
The final scan is of Ian Hopper in his mk3 Hopper special
and is from an advert in this years’ Classic Monte Carlo rally programme.
A picture of Ian Hopper in his mk3 Hopper special at the Rest and be Thankful |
It’s wonderful discovery and really useful. Thanks for the posting.
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