I have a 1972 455 that is not raced just local driving use. The bottom end is stock, M/T headers, Quadrajet cfm 800, 3.42 gears,Buick ready to run 8552 and MSD 6A series. Reed cam 220 TM 282XLH310 112A2H- 12" Torque converter 2500 stall. I need to knoe what springs & bushings to use. Do I use vacuum Advance? Where to set the timing? I have cam specs if you need them. Thank you.
The 8552 Distributor comes out of the box with a Blue bushing and the slowest springs (heavy Silver ). That gives you 21* of mechanical advance. If you run 12* initial timing, you'll have 12 +21 = 33* at WOT. When you set the initial advance, do it with the 2 heavy Silver springs installed, and have someone put the car in gear. You don't want ANY mechanical advance in when you set the initial to 12*. It helps to lower the RPM while setting initial advance. After you set the initial timing, try 1 Silver (light) spring, and 1 Blue (light) spring. That should give you full advance at 2500 RPM. Leave the vacuum advance disconnected, and make some full throttle pulls from various speeds. Listen for any audible ping. If you hear any, put the next heaviest springs in, and try again. If you can't eliminate the ping with heavier springs, reduce the total advance down to 32, and try again. Once you have that all sorted out, connect the vacuum advance and check for part throttle ping. All this is in the instructions which I hope you read. If you have part throttle ping with the vacuum advance connected, you have two options. Pull the vacuum advance canister and make a limiter plate just like the pictures describe in my Power Timing thread, or put in heavier springs to delay full mechanical advance. http://www.v8buick.com/index.php?threads/power-timing-your-buick-v8.63475/
