I've never paid much attention to the relationship of drill bit size and drill speed, having a tendency to stick a bit in the chuck and drill away at the highest speed the drill will go.
Well, you can ruin a lot of bits that way - or even worse, screw up a project.
I recently got smart on this subject in conjunction with a gun building project. And man, does the proper drill speed make a difference. The correct speed makes the work go faster with cleaner holes and longer lasting bits.
So if you're going to be doing any drilling on a gun, barrel, stock, etc., I recommend you get smart on bit size & speed.
All you need to do is GOOGLE "drill bit speed chart" and you will get a bunch of options.
Here's one I found really handy, and you can download the PDF format.
http://images.meredith.com/wood/pdf/...peed-chart.pdf