360 timing

The dist. is not currently locked out. When a dist. is locked, it can no longer do any advancing. Its a set it and forget it thing, best suited for drag racing, or engines with very big cams. We may lock it out later, depending on the results from what the engine wants for timings, but I dont like to do that on street cars.The vacuum advance function is very useful, as I have learned.
-And Ted if youre going to replace the vacuum can, you will want to get the one with the biggest number on the arm that you can find. I have never found one higher than 20*.It will not be the factory one listed for your engine.The LA small blocks all use the same type of can and are interchangeable. So happy hunting.
-And if anyone out there has found a can in the 24 to 30 degree range, I would sure like one,and probably, so will Ted.
- But Ted, does your can hold vacuum at all? That is to say,can you suck on the hose attached to the can, and suck and suck,endlessly pulling air into your lungs. If so, its done. This can be done on a running engine, and the idle speed will usually change if the can is functioning. If no change is noted, its likely done. By the way, your lungs will have to generate in the neighborhood of 18 inches of vacuum for this test.No one can do it in one pull. At least I doubt anyone can.You need to do it in stages. That is suck on the hose,bite the hose,suck and bite, continue as far as you can. You probably figured that out, but its fun to see in print.
-And to 4spd; its often possible for the carb to be pulling vacuum at the sparkport well past 3000rpm or more, when in Neutral/unloaded. This is because very little throttle is required to get there without a load on the engine. This is especially so as c/r goes up, as efficiency is also then rising.