Champion radiator install with twin electric fans

Cudaspaz-running painless 185* thermostat switch kit witch turns both fans on. both fans have there own 40 amp relay with 30 amp thermo fuse.Have a 70 amp alt that is not keeping up with all the currant draw.Think a 100 amp from March performance would work.With elec fuel pump,both fans,MSD the amps are 12.9 at around 2000 RPM12.20 at idle.Not enough to charge batt.