help. 1985 Evinrude 120 vro looper<br />replacing tachometer in dash.<br />My old tach is set on ALT.<br />The new tach is an isspro alternator tach<br /><br />Instructions say:<br /><br />NUMBER OF ALTERNATOR FIELD POLES:<br />8 PULLY RATIO 2.6 to 5.4<br />12 PULLY RATIO 1.7 to 3.6<br />14 PULLY RATIO 1.5 to 3.1<br />16 PULLY RATIO 1.3 TO 2.7<br /><br />ADJ TO NUMBER OF ALT FIELDS.<br /><br />anybody know the answer so i can set tach?<br />Thanx in advance. 