What do the Initial and final boiling point of a race fuel determine in reality. I'm having some knock issues. The car was tuned on C16

Specification Sheet: VP C-16

Specific Gravity: .735 @ 60°F

Lead: Leaded

Color: Blue

Motor Octane: 117

RVP: 1.85

Oxidation Stability (min.) 1440+

Distillation:
10% evap @ 211.5°F
50% evap @ 213.1°F
90% evap @ 215.8°F
E.P. @ 233.3°F


but I'm running This:

Specific Gravity 0.715
Antiknock Index (R+M)/2 112
RON, Research Octane 114
MON, Motor Octane 110
Reid Vapor Pressure 8
Distillation, ºF
Initial Boiling Point 90
10% Evaporation 155
50% Evaporation 215
90% Evaporation 235
Final Boiling Point 260
Oxidation Stability, Min 1440+
Copper Strip Corrosion No. 1
Existent Gum, mg/100ml 1


Whats the difference?

Also what would this fuel below do differently?


Specification Sheet: VP Blue

Specific Gravity: .717 @ 60°F

Lead: Leaded

Color: Blue

Oxidation Stability (min.) 1440+

Motor Octane: 108

R+M/2: 109

Research Octane: 111

RVP: 7.20

Distillation:
10% evap @ 140.1°F
50% evap @ 214.0°F
90% evap @ 248.4°F
E.P. @ 389.3°F

 

Maybe just get some 1600cc injectors & tune for alcohol?

I just run 93 and go a little slower.

Maybe the guys in the race forum will have a clue.

 

Hmm I'm running 1600's hehe, I'm not leaning out either.