I am thinking about purchasing or (likely renting) a set of wheels for Ironman Lake Placid and am wondering if anyone can help me figure out what sort of benefit I might receive from a set of race wheels. I looked online and don't see any great information for someone who is not cranking out an average of 300 watts.
So, here is my story. I weight about 170 pounds, with a set of box wheels, if I keep my heart rate where I want it to be for the duration of the bike it looks like I will finish the bike in between 6:30 - 7:15 averaging between 15.8-16.8 mph depending on the windspeed and weather conditions (I have ridden the course a couple of time and these numbers should be fairly accurate).

I am looking at either a set of firecrest 808s or an 808 rear and 404 front. I was wondering if anyone could provide insight into what, if any time I might save (or speed I might gain) given my weight and predicted speed with the boxed wheels?

Best and thanks in advance for any help,

Dave