It's hard to say without knowing drivetrain losses. I don't think 12% loss is way off the mark for a manual trans in a FWD car.
Hatch Nation #90
'12 SE Sport 5Dr |╠╬╝|Sterling Grey Metallic|203a|Moonroof|17" Paint/Mach Whls|K&N 57S-4000|FFE RMM|Steeda STB, RSB|JBR bushings
'01 ZX3|╠╬╝|Pitch Black|Prem. pkg.|Moonroof|SVT Snorkel|SVT Springs|S2 Dampers|Steeda STS|Magnaflow exh.