Pings like crazy.
Thread Starter
Instructor
Joined: Mar 2007
Posts: 223
Likes: 0
From: Henryville Indiana
Pings like crazy.
Got a 79 w/a 406 and the motor pings like crazy any time I get on it.Doesn't matter if its hot -195 or cold,it still does it.Set total timing to 32 degrees w/no vac advance and it still does it 93 octane,HEI advance is all in at 2850.12 degrees at the crank initial and and 20 more as the rpm comes up.
36 degrees was worse and the vacuum adv makes it sound like baby rattles.
HELLLLLP!!!!
36 degrees was worse and the vacuum adv makes it sound like baby rattles.
HELLLLLP!!!!
Pro
Joined: Jul 2002
Posts: 723
Likes: 0
From: North Port, FL
Got a 79 w/a 406 and the motor pings like crazy any time I get on it.Doesn't matter if its hot -195 or cold,it still does it.Set total timing to 32 degrees w/no vac advance and it still does it 93 octane,HEI advance is all in at 2850.12 degrees at the crank initial and and 20 more as the rpm comes up.
36 degrees was worse and the vacuum adv makes it sound like baby rattles.
HELLLLLP!!!!
36 degrees was worse and the vacuum adv makes it sound like baby rattles.
HELLLLLP!!!!
Last edited by ZL1powr; Aug 5, 2007 at 11:23 AM. Reason: correction
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
CR? Cam?? Heads??? Under what conditions???? Without more info none of us can help much.
...and do verify that your balancer marks are indexed properly, as ZL1powr alluded to. Could be running a lot more advance than you realize.
...and do verify that your balancer marks are indexed properly, as ZL1powr alluded to. Could be running a lot more advance than you realize.
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Intermediate
Joined: Aug 2003
Posts: 28
Likes: 0
From: henrietta texas
I had the same problem
My 78 with a 406 would do the same thing. After trying different things I was able to fix mine by-
1) Running a colder set of plugs, AC R43TS
2) My HEI had an adjustable VAC Advance Can so I slowly kept adjusting it until the pinging went away.
Runs great now no more pings.
Hope this helps
1) Running a colder set of plugs, AC R43TS
2) My HEI had an adjustable VAC Advance Can so I slowly kept adjusting it until the pinging went away.
Runs great now no more pings.
Hope this helps
Burning Brakes
Joined: May 2007
Posts: 945
Likes: 0
From: Ventura California
My 78 with a 406 would do the same thing. After trying different things I was able to fix mine by-
1) Running a colder set of plugs, AC R43TS
2) My HEI had an adjustable VAC Advance Can so I slowly kept adjusting it until the pinging went away.
Runs great now no more pings.
Hope this helps
1) Running a colder set of plugs, AC R43TS
2) My HEI had an adjustable VAC Advance Can so I slowly kept adjusting it until the pinging went away.
Runs great now no more pings.
Hope this helps
Instructor
Joined: Jun 2006
Posts: 123
Likes: 0
From: Westminster MD
Do as ZL1powr says and verify your timing mark! I bought a piston TDC stop (SUM-900189) from Summit for $6.95 the best money I ever spent on a tool. I had the same problems as you, I gave up on vacuum advance and had a rattle everytime I step on it (thought it was the manual chock cable hitting the air filter base - wrong). Turned out that the timing mark that my car was tuned to was wrong. The harmonic balancer had two marks about 38-40 degrees apart. What a difference, just ran 0 to 60MPH in 5.7 seconds with no rattles or pings.
Thread Starter
Instructor
Joined: Mar 2007
Posts: 223
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From: Henryville Indiana
Engine was asssembled and running before I got the car.No idea on cam,slight lope,last owner said he remembers something about 268 something,his words,not mine.That tells me a 268 degree @.050 cam.Would account for slight lope in idle....Compression NFI no idea on pistons
441 heads.No headers,just 2 1/2" with Flowmaster 40s.
Stock style intake from a later model,poss 305.Pings without vac adv hooked up as well.
Any acceleration more than slight will make it ping.
R44TS plugs at .043 gap.
Got to get TDC figured out...will try the TDC stop and get a degree tape for the balancer.Might have WRONG front cover and/or pointer.Just realised that some of the tin may be from the old L-48.
441 heads.No headers,just 2 1/2" with Flowmaster 40s.
Stock style intake from a later model,poss 305.Pings without vac adv hooked up as well.
Any acceleration more than slight will make it ping.
R44TS plugs at .043 gap.
Got to get TDC figured out...will try the TDC stop and get a degree tape for the balancer.Might have WRONG front cover and/or pointer.Just realised that some of the tin may be from the old L-48.
Last edited by R96IMP; Aug 8, 2007 at 12:18 AM. Reason: typo
3rd Gear
Joined: Jul 2007
Posts: 3
Likes: 0
From: Puyallup WA
Only pings under load?
I just had a tune up done on the car, and they said they checked my timing and reset a few things and everything was great now, but on my drive home, I have a pretty steep hill I have to drive up.... everything was running and sounding great until I go to the hill, and then I started to hear some serious knocking as the engine took on the heavier load.
I'm guessing the vacuum advance is too great ... but still trying to get a handle on the whole timing thing... trying to understand all the different settings.
Am I on the right track at least? Should I just retard the timing by *2 and run up the hill again to see if the knocking goes away?
I should also mention that I had no knocking issues at all before the tune up....
Thanks!
I'm guessing the vacuum advance is too great ... but still trying to get a handle on the whole timing thing... trying to understand all the different settings.
Am I on the right track at least? Should I just retard the timing by *2 and run up the hill again to see if the knocking goes away?
I should also mention that I had no knocking issues at all before the tune up....
Thanks!
Thread Starter
Instructor
Joined: Mar 2007
Posts: 223
Likes: 0
From: Henryville Indiana
Found the problem!!!!!!
Remember I said the engine was already together when i got the car????
Who ever put it together,put the timing pointer in the WRONG 2 holes on the front cover
......wonder what else????
Remember I said the engine was already together when i got the car????
Who ever put it together,put the timing pointer in the WRONG 2 holes on the front cover
......wonder what else????
Thread Starter
Instructor
Joined: Mar 2007
Posts: 223
Likes: 0
From: Henryville Indiana
Simple is a relative term.....Still have to pull the WP and fan to correct.Wish I had a clutch fan(7 blade)ready to go on.Gee guess I could upgrade to the aluminum pump.....What's better,the Edelbrock or the Stewart???
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Yeah, I should have said "relatively simple". At least it wasn't something fundamentally wrong with your engine's setup.
Those same two pumps you mention are at the top of my list. Dont' know if it's "better", but I'm planning to install an Edelbrock Hi-perf on my 496.
As for the fan, you could always go dual electrics.
Those same two pumps you mention are at the top of my list. Dont' know if it's "better", but I'm planning to install an Edelbrock Hi-perf on my 496.
As for the fan, you could always go dual electrics.
