I have an all aluminum 496 FE with solid roller with 10.7 compression (93 pump gas) built by Keith Craft. He told me to keep it at 40 total advance where he dyno it and it made 681 HP (run rpm up until it stops advancing 3,000 or so) and set it at 40. Mine idles around 900. I've run a bunch of big small blocks at 34 and 36 and was nervious about 40 degrees on this big block so I backed it down to 36 and then 38 and it ran hotter and not as good. Put it back on 40 and Keith was right that they like a lot of timing as it starts great, run much cooler and outstanding power and drivablity!
