No Guarantees, but the following helps with low octane fuel:
1. polish the combustion chambers (might as well do some porting while your in there if your doing it yourself).
2. retard the timing (but has a negative effect on performance)
3. install a water injector system.
use closed chamber heads with dish top pistons = about 10.3 comp ratio. stellite exhaust seats. chamfer combustion chambers(2mm chamfer) for mild street try crow cam #21665. single plane intake(great with gas even on stock engine) re curved dissy, electronic ignition. impco 425 mixer on 750mech holley base/throttle body. impco model L or equiv convertor. interference extractors with twin 2.25 inch exhaust. that will give you a relativly cheap but strong reliable combo that will go quite well and run auto, air, power steer ect if u need. cheers