In fact I have never heard anyone tell me what the stock timing is in any saw,they have never checked it. No one in the rest of the performance world(cars,motorcycles,etc.) does not know where stock timing is or what it is when they alter it.
Trappermike Big Woods had a discussion about his 372s. He would take a 268 piston and machine it down to make a popup. The piston skirt is already shorter than the stock 372 piston and actually a lot lighter. The shorter skirt would obviously give it a bigger intake duration. He would keep the squish at .020-.024 and the compression no higher than 180. He would use the base gasket so the exhaust timing would stay the same. I have bought a few modded saws where the exhaust port is raised up and makes for a fast saw but loses much needed torque when your in big hardwoods. He also suggested putting a 385-390 carb on. I'm not interested in cookie cutters for my self just strong pulling saws. Although I do like watching saws fall right thru the wood at the meets. Everybody is looking for something different and that's ok. I do like reading your posts and getting what I can out of them. ThanksLong ago I made a mistake and my hotsaw engine had 220 psi compression. The ignition broke down and misfired badly about 12,000 rpm. I reconfigured it to be about 170 psi and then it ran perfectly to 14,500 plus.
Use what the mfg recommends - most say 89 ron. Rec 90 is good. The higher the octane, the slower it burns - to prevent pre-ignition.