If your strike water was 167 and you added a little over 30lbs of grain, it should have definitely dropped it below 167. How did you take your temps, and I'm assuming you weren't heating the mash at all during the 60 min?
If you actually did mash at 167, you're going to have a very unfermentable wort. I've never mashed that high, but I would think your efficiency would still look the same (maybe better since its warmer), but you've denatured a lot of the amylase (beta?) that works at lower temps. The wiki article on mashing
says you can expect about 55% attenuation from a mash that high. Check your technique first and make sure you actually mashed that high, but you may want to consider some amylase to bring it down a little, or some sugar to up the OG and dry it out a bit.