How to rebuild and blueprint a GM HEI

With before and after video footage of my 1974 Z-28 muscle car. Other items changed were; spark plugs and a larger mandrel bent exhaust system. The above added 25 to 35 more HP and increased Torque at the engines crankshaft. According to my Moroso Power Speed Calculator this should lower 1/4 mile ET's by close to 0.5 seconds depending on, Track conditions & "IF" the tires will stick/hook-up. The car had no traction problems before this mod. Now It goes up in smoke during a launch. I'm running 91 octane Non Ethanol premium fuel. GM recommend a minimum RON octane of 93 leaded fuel. this would require 100 octane racing fuel. This would allow the engine to run 38º total timing advance above 3500 RPM without knock, I had to reduce TTA down to 34º to prevent knock (detonation) and dieseling...