Slight pinging/vacumm advance

[Broken_down?]

1. When I hit a steep hill I get a small pinging. Only under a good size load on engine. Like starting out in middle of a mountain pass. Timing is fine. @ 5dg.
2. I read a post about removing the vacumm advance line and driving it that way.? Will this work? Idle seems fine but at times will rise and fall. slightly.

Any ideas ??

Rich

[COBALT]

Points or HEI?

5 deg with vacuum advance or without? Either sounds like not enough advance to me. Usually I set my 350 between 10-15 with the vacuum advance disconnected.

[Virginia72SWB4X4]

Broken

Are talking about a SB chevy? 5 dg doesnt sound like enough. Typically if you set your total advance, that is all advance both centrifigal and vacumm when the engine is at about 2500 rpm to between 36-38 degrees you'll be very happy with it.
The 10 degrees a typical SB is set at at idle has little to do with overal drivability. The engine normally only sees that at idle or near idle.

Also pinging (or pre detonation) can be caused by dirty valves or carbon build up. Try a can of BG 44K. Its expensive about $18 a can but believe me it works.
Hope it helps

[WRMZ71]

I had a problem with valve pinging at heavy acceleration or under load and i had to run premium to shut em up. I had my timing set at 12 BTDC. What I found out though is that I think my harmonic balancer mark is off so when it was reading 12 it was more like 8 or lower. I just advanced it aways and now the pingings gone and i can run the cheap 87 octane in it now. If you wanna call gas cheap

[Broken_down?]

ok I do not have a dwell meter, so I cannot set the dwell. I have Points. By advancing the timing it should make th epinging stop?

rich