Many years ago, when I went thru 235 in my 54. 1 of my fan blades was cracked. I thought it better to run without fan than take chance of it coming apart at speed. Difference was very slightly noticable but truck would start to creep a bit warmer when sitting still at a stop light. I got another fan and it has been running as it should for years. bottom line is very slight but noticable gain from engine not having to turn fan but not worth it in my opinion.