I don't have links on me but what I've seen/heard over the course of the year:
Mclaren - 765BHP BMW - >750BHP
Ferrari - was 752BHP before updates, now around 770BHP
Renault - 725-740BHP (guess) Toyota - ~740BHP Honda - >700BHP
There's links for 3 of the engines. I got the Mclaren and Ferrari info from a F1 engineer on the AtlasF1 BB so I can't confirm those (I can't find the post).