Ok, understood now. I didn't think it was the timing belt either: while
it would crank faster, it would never start. Yours starts, so that
can't be it.

The fast cranking is just weird or maybe I misunderstood what you
meant: is it starting normal or a lot faster than normal? A lot faster
would indicate some mechanical load change.

Let's start with the absolute basics: are you sure you are getting a
good hot spark and have good fuel pressure?
When it starts, do you see a huge puff of smoke (indicating perhaps
flooding)?