Timing issues moving from a 5v 16Mhz device to 3v3 8Mhz?

Hi all.

I want to swap out a 5v 16Mhz pro mini for a 3v3 version.

Am I likely to see any timing issues - I guess a millisecond is still a millisecond but the code will just be doing less cycles than running at 16Mhz?

I have This code running fine on the 5v 16Mhz chip

Should be no issues. The bootloader takes care of all the timing differences. Shouldn't see any changes.

I'd be most worried about all the libraries - check they each work at 8MHz indepedently first so you know the score.