I think they are about the same power if it's power-weighted Perfect Cell which was shown. If Cell hadn't suffered any injuries, I'd say his weighted power would be about equal to his Super Perfect power, since I generally think Cell being weakened by the beating would spoil his weighted power too. Something like this...
FPSSJ Goku (Cell Games) - 50,000,000,000
FPSSJ Gohan (Boo saga) - 50,000,000,000
FPSSJ Gohan (Cell Games) - 66,000,000,000
Perfect Cell (full power) - 200,000,000,000
Perfect Cell (power weighted;already injured) - 250,000,000,000
SSJ2 Gohan (Boo saga) - 250,000,000,000
Perfect Cell (potential power weighted) - 310,000,000,000
Super Perfect Cell - 310,000,000,000
SSJ2 Gohan (Cell Games) - 330,000,000,000
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Goku (bursts against Ginyus) vs future Trunks base (age 14)