[sean70ss]

On my 706 we use 24 degrees timing on the 588 that I have in my chevelle we use 33-34 no more. The more timing you use will cause detonation. The bigger bore is actually more forgiving then the small bore less quench. Smaller motors like more timing. Lower octane will cause detonation it explodes before it hits top dead center. Higher octane has a slower burn rate which will make more power so lets say you had 11.1 427 you used 93 ocatane with 36 degress total advance it would more then likeley ping itself to death but if you had a mix of 93 and 116 and 36 degrees it would not because of the slower flame travel. I had built a 555 a few years ago i wanted a street strip deal. 12.1 compression I ran 93 octane and vp 116 50/50 it made 893 hp on the dyno with 18 degress initial and 35 degrees advanced! I figured 50hp less in the car due to air and humidity. So basically these cars are not driven that much so give them some good fuel they will be much happier and live alot longer.