How to Increase C-score? and accuracy on local I-Tasser 5.1

Hi,
I have tried same sequence on both local I-Tasser5.1 and web I-Tasser. I realized my C-score for the same sequence model 1 on both web and local is a bit different. For example on web I-Tasser I might have -1.74 but the local I-Tasser5.1 might have -2.7 C-score. Is there any setting I can change to increase the C-score on the local I-Tasser5.1? The setting I have for local I-Tasser 5.1 is -light -hours 20, which is the closer structure to the Web I-Tasser result. If I use default setting 50 hours the structure looks very different and with a very low C-score (model 1), but model 2 is similar to the Web I-Tasser, but with a low C-score (-3.6). Thank you for your time to read this message.

Kind Regards,
Heng Ku