It's all on the ratios.
Stock
Wp = 6.88
Crank = 6.56
5% under driven
CVF
Wp = 6.38
Crank = 5.25
21% under driven
PLUS With a crank pulley that small the alternator pulley will be reduced in speed
From overdriven by 62% to overdriven by only 52%
That's like putting a 3 to 3.25 pulley on the alt with the OEM crank pulley. You will have crappy charging at idle, If any. At 600 rpm crank you alternator will only be spinning at about 900 RPM.
