Need Advice! Do I Need a New Camshaft????

[Atlfan65]

Originally Posted by weq92f

According to the article quoted above...you'd be adjusting the tip-in point of the can's full vacuum movement from about 4.5 to around 8 inches of vacuum with one turn and 8 turns respectively.

-klb

What are you seeing in that article that mentions specific numbers? It talks vaguely about the concept of vacuum advance and mentions the limiter plates, but doesn't talk about what adjusting the vacuum advance can does. Point it out to me if not. I'm looking at section 15.5.

I'm confused what you mean "tip in point at 4.5 in - 8 in vacuum." My truck is running at 20 in vacuum at idle and while I didn't have long enough vacuum line to test cruising vacuum, I'm sure it's much higher than 8 in vacuum.

What I've read about tuning vacuum advance says to back out on the vacuum advance adjustment if pinging occurs. So what is this physically changing?