Dhorn33

I just built my bike - it is an 84 Bianchi Alloro with Shimano Ultregra 8 speed STI stuff. Anyway - the cassette is one that I took off my 92 Paramount 650c wheeled bike - and I know it has an 11 tooth small cog but I am not sure of the large - but it is definitely smaller than a normal 700c wheeled bike has. I do some hills on my rides around here in MN and I was challenged this weekend going up a long hil even in the lowest gear combo so I was thinking maybe I would find a more standard cassette to try. What is the recommended 8 speed cassette gearing? I really like the 11 tooth rear for speed downhill but I need a little something extra on the low end. Any suggestions?