Public Pool Flow & Turnover Problem

[watervale]

[ Note to posters: this is a public pool. Very different rules apply! PoolDoc. ]

I'm getting about 80 gpm. I'll never get to the 244 gpm required to turn my pool in 6 hours. I would, however, like to improve upon the 80 gpm.

88,000 gallons, two 500 lb sand filters, 2 hp and 1.5 hp pump. Two 3 inch pipes return from the skimmers and bottom (1 pipe for each). Pipes drop to 1.5 inch before each pump. Each pump feeds a filter (1.5 inch pipes) and then the pipes combine again in a 3 inch junction.

Each 1.5 inch pipe should theoretically give me 74 gpm. Filters are rated for "up to" 98 gpm. I should theoretically be able to achieve 140 without changing pipes or filters (I think).

Before I spend the money, I am trying to figure out if larger motors on my pumps will give me extra flow. Are my assumptions above incorrect? Any thoughts?

Russ