Hi Lindsay,
According to my mate Alan Cooper who had/has a Flavia 2000HF Coupe, Don't do it!
"My experience with a 2000HF was that 5W is way too thin caused hot start knocking I think Lancia actually recommended 10w40 but allowing for a bit of age and wear I would guess 15W50 may well be better. The 2000 seems prone to oil supply problems at start up more so than a fulvia, presumably due to the engine layout. It is also important that you use a good quality filter such as technocar (if they are still available) I'm not sure that anyone else still does a specific filter for fulvia/flavia fram used to do one (ph2803-2 if memory serves me right) but I'm sure it's discontinued a non-drain bowl is critical, in the event that you do get knocking at hot start try changing to a different filter make."
Brian
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