Timing Question
Thread Starter
Joined: Apr 2002
Posts: 1,136
Likes: 1
From: Fayetteville, NC
Car: 84 Z28 Convertible 2 Seater
Engine: Dart Little-M SBC 400
Transmission: Pro-built Automatics 700R4
Axle/Gears: Strange Engineering 3:73
Timing Question
My timing mark on my Harmonic balancer do not line up with the chrome timing tab I bought from Autozone at top dead center. Its about 4 degrees atdc off. What is my option for getting this tap or balancer to be in the right position and yes my timing marks are right my Cam sprocket is at the 12:00 o'clock, and Crank sprocket is at 12:00 o'clock position.
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Joined: Jan 2000
Posts: 19,659
Likes: 310
DTL,
While not the "eleventh Commandment", it has been my experience on every SBC I can remember that the ignition timing groove on a stock damper is ALMOST lined up with the keyway. I've stated that the mark is relatively "lined up" as a reference when trying to find TDC or determine if the damper is really slipped. From the best I have been able to measure with a degree wheel, the timing groove in the outer ring is actually retarded 10˝° from the keyway position in the hub.
If your timing groove is slightly retarded, I'd suspect that the aftermarket timing tab is not accurate. Hell, I'd suspect anything from AutoZone, anyway...
BTW - I've got an aftermarket chromed timing tab and timing cover on one engine, and I know it was off before I modified it. I just don't remember how much.
While not the "eleventh Commandment", it has been my experience on every SBC I can remember that the ignition timing groove on a stock damper is ALMOST lined up with the keyway. I've stated that the mark is relatively "lined up" as a reference when trying to find TDC or determine if the damper is really slipped. From the best I have been able to measure with a degree wheel, the timing groove in the outer ring is actually retarded 10˝° from the keyway position in the hub.
If your timing groove is slightly retarded, I'd suspect that the aftermarket timing tab is not accurate. Hell, I'd suspect anything from AutoZone, anyway...
BTW - I've got an aftermarket chromed timing tab and timing cover on one engine, and I know it was off before I modified it. I just don't remember how much.
Thread Starter
Joined: Apr 2002
Posts: 1,136
Likes: 1
From: Fayetteville, NC
Car: 84 Z28 Convertible 2 Seater
Engine: Dart Little-M SBC 400
Transmission: Pro-built Automatics 700R4
Axle/Gears: Strange Engineering 3:73
Here is what I did a old trick taught to me a long time ago. I removed the number one spark plug and put a piece of crumble newspaper in the number One cyclinder. Turn the crank clockwise until that piece of paper shot out and my one one piston was up. After that I drop the Distributor in and the rotor was pointing at the number one plug. Is this a good method of getting the engine top dead center. I must admit the paper did shoot out a little before the marks reached 12 o'clock Cam to 12 o'clock Crank. Should I have just stop there or kept turning until the marks was lined up.
Junior Member
Joined: Apr 2001
Posts: 55
Likes: 0
From: NJ
i got the same tab yur talkin bout. i got rid of that. that thing is way of.matter of fact i broke the stupid timin cover. its better of to use the stock cover with the tab welded on there. but i did put the balancer mark on 0 on the chrome tab yur talkin bout. it started it fine. but i dont trust it. once u take a timing light to it is way of .
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