Q:

Potential Max CP of Wild Pokémon

I noticed that somebody had a Pidgeot with a far higher CP than mine, which was maxed out for my level. Initially I thought that was just because I was a lower level trainer at the time - I was around 8 and he was about 20. But later on I thought that the difference (500cp versus 1200cp) was too big to be made just by leveling the trainer.
I began to think that maybe the CP of the Pokémon when they are caught makes a difference. Previously I had assumed that they would just need less.powering up to take them to max if they had a higher CP, but does a Pokémon's starting CP affect their max CP cap later on?
For clarity, if I found a 10 CP Pidgy and a 100 CP Pidgy, will one of them have a lower max CP cap or could I raise them both to the same level in time?

A:

Actually the difference in the CP is not too big for it just to be trainer level and is quite normal. A pokemon's starting CP will never affect their max CP cap because the cap moves with trainer level.
However a 10 CP pidgy with a higher IV than 100 CP pidgy will have a higher max CP cap simply because it has better base stats.
Link for IV calculator is here.

