Sorry if this has been covered before, a quick search can't find it. Can I fit an engine that has no engine numbers? Does it pose major problems?
What engine and it could well do if your iva'ing it
Bike engine most likely, though I suppose it's also a theoretical question - what if you made your own engine (unlikely but possible). Yes, for IVA purposes. I heard somewhere that, like the chassis, providing you could identify the engine as being from a specific model you could effectively stamp your own numbers on it, but I questioned this naturally.