I see evidence as the observations which have been established. Things are offered in evidence - a log book, a photo, a receipt of purchase with description.I can see both sides of this.
Evidence...........False Evidence. (is it still evidence)
Testimony....….False Testimony (is it still Testimony)
Tits..................False Tits (are they still Tits)
But if the log book contains the wrong information, it changes from evidence of the model/engine/etc., to evidence of the description under which it was purchased and that the log book was wrong. A photo might show a blue Ascona with the appropriate number plate. Which is common ground regardless the engine. Another photo showing the actual engine might help to establish the capacity. But it has to be established that it really is a photo of the engine in that car.
It isn't so much that evidence has to be true (i.e. if the log book is untrue it ceases to be evidence at all) as that the interpretation is based on the truths taken from the evidence. The log book's evidential value changes depending on whether its content is believed or disproved.