Originally Posted by crrushing
Thanks a lot Pog, I have set it at 8* BTDC at 1600rpm kinda like what it says under the hood. I just assumed that was the correct way to do it because i could not find anywhere that it specifically said time it at idle. And thanks for the clarification of the spark is same as ported vacuum. It is all clear now.
Glad I could help. There is tons of info in these forums and some great write-ups. However, many times the small details get left out. The emissions sticker under my hood stated the same thing about setting the idle at 1600 RPM. That would be true if you had not done the Nutter. The Nutter basically reverts your ignition system to a 1980 "Pre-Emissions" setup by bypassing the ECM and moving your distributor advance from manifold vacuum advance to spark (ported) vacuum advance on the carb. As a result, you must try and duplicate how a 6-258 setup would have run in 1980 or earlier. That means setting your timing around 8* BTDC at a 700 RPM curb idle +/-20 RPM. This in itself is still not law, but just a good starting point. Many setups, especially ones that have also been "Team Rushed" can run their timing advanced up to 12* BTDC without any problems.
Mine being Nuttered and TR'ed runs great around ~9-10* BTDC with no issues.