OCTANE RATING CHART

Compression Octane rating
Up to 180 psi. 93 s.u. pump gas
180 – 200 psi 100
200 – 210 psi. 105
210 psi. & up 112 or higher

 

TIMING DEGREE CONVERSION CHART

Degree

BTDC
550 650 750
17 .065 .079 .079
18 .075 .089 .088
19 .085 .099 .099
20 .095 .109 .110
21 .105 .119 .123
22 .115 .130 .134
23 .125 .148 .144
24 .135 .159 .158
25 .145 .169 .169
26 .155 .175 .181
27 .165 .195 .197
28 .175 .210 .213

 

RECOMMENDED IGNITION TIMING CHART

Stock Timing Recommended Timing
440 P.P. all 28 deg 26 – 28
550 P.P. 82-85 – 28 deg 26 – 28
550 P.P. 86-90 -21 deg 26 – 28
550 reed Kawasaki 21 deg 26 – 28
650 all  21 deg 21 – 25
750 Total Loss 21 – 24