6-71 vs. 8-71

Well, my initial thoughts were that I would probably run around 10 pounds of boost for normal driving, but I would kick it up to somewhere between 15-20 at the track when I have race gas available. From what I saw on the BDS website it seems to depend on what 6-71 I would get (small bore or large bore). I think the small bore might have a hard time, it would put out 10 pounds 1:1, but I would have to overdrive it pretty much all the way to get over 15. The big bore 6-71 looks to be almost the same as the 8-71. I can tone it down to 10 pounds with underdrive and at 1:1 it's making a little over 15. Granted all of this is just off of BDS's charts, so there's no real telling till I build the engine how much boost I would make. I was also looking at a different brand (Dyer's), so I don't know how the BDS chart compares.