11:1
I don't know on the injectors - I'm emailed Jenvey with the info and asked for their thoughts.
I can ask for the lambda plot - not sure he has that printed out...
What wasn't helping were the foam air filters that were getting sucked into the trumpets and making the mixture rich at the top end so on the French graph, you'll see :
sans FA = without air-filters (pink) with engine cool and cooler air
Avec FA = with air-filters (light blue)
Test20 = without air-filters, later run with engine warm with warm air
The engine tends to run more hot than warm - something else to check out.