Is 8 degrees timing chain slack bad?

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warlord
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Posts: 155
Joined: Wed Apr 01, 2009 12:24 am
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Year: 1983
Model: Trans Am
Engine: 305
Name: Richard Funnell
Location: Shoreham By Sea, W. Sussex
Location: Shoreham By Sea, W. Sussex
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Is 8 degrees timing chain slack bad?

Post by warlord » Sun Feb 14, 2016 5:22 pm

I've tested the timing chain on my 305 by rotating the engine by hand clockwise to 0 on the timing pointer, then anti clockwise till the rotor moves. I get 8 degrees before the rotor moves. I know this is bad, but is it worth the expence on a tired engine?
i mean when i do it, will the engine run any better? or won't i notice anything.
Also i get a steady 16in hg vacuum and when i did a compression test the other year, the lowest was 155psi and highest 160psi. I have the ignition timing at 22 degrees, if i set it at stock 6 degrees it runs terrible

maybe i'm paranoid, but i'm just not sure what is the best thing to do.
Thanks
"Conquest is made of the ashes of one's enemy's" - Starscream.
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1983 Trans Am 305 LG4
Member: 20443 - Richard

jonbullnose
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Re: Is 8 degrees timing chain slack bad?

Post by jonbullnose » Thu Feb 25, 2016 2:16 pm

will have some slop in the timing chain / train side of things, the engine only runs one way so not really a great test to do to be honest in the real world ,if you still have the original bonded vibration damper it may well have moved a little on the bonding seen it before hence looks like its running dif timing also depends on the engine having any modified internal parts, have you put a piston stop tool in cylinder 1 and then checked the timing marks at tdc are 0 as long as the timing is stationary when running i would not worry

warlord
POC Jr. Poster
Posts: 155
Joined: Wed Apr 01, 2009 12:24 am
Membership No: 20443
Year: 1983
Model: Trans Am
Engine: 305
Name: Richard Funnell
Location: Shoreham By Sea, W. Sussex
Location: Shoreham By Sea, W. Sussex
Contact:

Re: Is 8 degrees timing chain slack bad?

Post by warlord » Tue Mar 15, 2016 10:06 pm

I don't think the timing wandered last time i checked it. i will get a piston stop and check that. thanks
"Conquest is made of the ashes of one's enemy's" - Starscream.
Image
1983 Trans Am 305 LG4
Member: 20443 - Richard

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