The short answer is yes. Dual 14” fans will draw upwards of 50 amps and your stock 55 amp alternator is probably taxed to provide sufficient output. Once the engine is running, the battery is no longer in play here. I’m making an assumption that this is in your 37 Ford and as such you do not have room/clearance to use the standard clutch fan and shroud. As such, you will definitely need to upgrade your alternator. I have used Powermaster 67293 alternators on multiple builds and have been very satisfied in terms of appearance (polished aluminum) and performance (150 amp). It will set you back north of $150, but is a great one-wire replacement unit.

Make sure to install a bonding strap directly from the back of the alternator (lug is provided) to bare metal on the frame or engine.

Regards,
Glenn

Install a #6AWG stranded copper cable directly to the battery https://www.summitracing.com/parts/sum-810002 or similar).

As a side note – it is NEVER a good idea to replace a GM OEM clutch fan and associated shroud with electric fans unless absolutely necessary for clearance.