E10 fuel...

[Paul N-M]

I see the FBHVC are asking about our cars and the introduction of E10 fuels here: https://paulc1.typeform.com/to/Bt7HKS

My own experience is that I used E10 exclusively for our tour around France this summer - the car ran perfectly on it for 2500 miles and returned 35mpg despite the weight it was carrying (GW of just under a tonne). I have used petrol containing ethanol in all the Austins since it was introduced and have never suffered any issues. 4 years ago I undertook a trip to Switzerland in the Pearl alternating 98 and E95 octane fuel each day. It misfired (almost pinked) on the 98 so much in the heat that after 4 days I reverted to E95 exclusively. I have asked several times on Forums if anyone can attribute issues in use of their A7 exclusively to the addition of ethanol but have yet to hear any replies. Plenty of worry about the potential issues but nothing, as yet, which is substantial. Has anyone here suffered something in their A7 which they can evidence back to Ethanol - genuinely interested?

Sadly I cannot give firm proven evidence but this is my take on the matter.

Ethanol absorbs water vapour so fuel will go "off". My solution is to add "Millers tank safe" when leaving a car say for a period like winter.
Treated in this way I can say with certainty that the fuel is still good after three years. The more important aspect is that the tank does not then rust, I personally choose to fill the tank full for lay up.
I also choose to put an additive - VSP in the fuel for normal running This is both an ethanol killer and lead additive in one. I think the ethanol killer of which there are many brands is a good thing, the lead side of it is probably not really needed in a Seven.
 
If you are working the engine hard, plugs are then fine but, and it is a but if you drive easy I believe you now need a hotter plug. 
I have had quite a lot of experience of this plug failure in different chums cars. The result of which in some cases has caused mag failure. With this fuel once a plug misfires I believe it is not easy to clean back into service.
Oven cleaner seems to be the only stuff or of course a proper plug blaster.

For general info. Tetra Boost has been formulated to prolong petrol life with up to 15% ethanol as well as put lead in the fuel. It does not stop the ethanol attacking non compatable materials. I use it in my Bentley and Austin specials and it definately helps.