I'm Not An Expert, But...
I'm pretty sure this 200K BTU York with an 8 ton drive requires more than a single side 16x25 return.
Good? Bad? I'm the guy with the gun.
Statements made by me are strictly my opinions and do not reflect the opinions of my employer. I am not authorized to make any official statements on behalf of my employer.
Any technical advice offered by me is for educational purposes only, all HVAC related repairs should only be attempted by qualified personnel.