Are there any limits to how many Boost or Setback dice can go into a pool?

I was looking at the "how to build a dice pool" section on the AoR CRB, but I didn't see any limits imposed.

I don't think there is one and I usually stack them too.

Here's 3 setback for the Typhoon, he has cover, that's 1 more and don't forget you failed your fear check so it's 5.

Defence caps at 4, but that's the only cap AFAIK. And defence capping doesn't mean you can't have more than 4 setback dice on an attack, it just means only 4 of them can come from defence.

Ah ha! I knew in my head there was a cap at something.

Thanks!