Timing Chain
Le Mans Master
Joined: Apr 2001
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From: Was New Orleans but swam to Baton Rouge LA
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I don't give a **** what the video says or who says what. Dot to Dot is TDC #6. 12 and 12 is TDC #1. In both positions, the pistons on 1 and 6 are at the top.....but that is not considered TDC. I have built over 200 Chevrolet V8's from junk to 40k Big Chief engines and this applies to all. You can put it all together dot to dot and the mark will be in the correct spot but if you drop the distributor in pointing toward #1, you WILL be 180 degrees out. Always.
Jebby
Jebby
Is my vette stock?? HAHA
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How are you setting timing? Is your mechanical and vacuum advance working? Theres a number of things that can cause backfiring.
Is your backfiring out the carb and dramatic or just a lot popping out the tailpipe?
Is your backfiring out the carb and dramatic or just a lot popping out the tailpipe?
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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If it's out the carb I would think to much advance, if it's out the rear I would think it's super lean. If it's when your driving , foot off pedal and winding down on the engine then I would say too rich
Le Mans Master
Joined: Mar 2004
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From: Little Rock AR
Jebby is right about the firing position. Crank gear at 12:00 and Cam gear at 6:00 is TDC #6 FIRING position. #1 and #6 pistons are both at TDC but only #6 is in the firing position.
Le Mans Master
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From: Was New Orleans but swam to Baton Rouge LA
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Melting Slicks
Joined: Apr 2001
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From: Olmsted Falls, Ohio
Because the distributor never lost its relation to the cam. You installed the chain at #6....and when you did, the rotor was pointing to #6 terminal on the cap.....so no issue.
But if you pull the distributor.....and do dot to dot, then point the rotor toward #1 it will be 180 out. It has to be.
Jebby
But if you pull the distributor.....and do dot to dot, then point the rotor toward #1 it will be 180 out. It has to be.
Jebby
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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wrong again....Like I said, pay attention to the manufacturers instructions. 6 and 12 is #1 tdc for a specific chain, Comp Cams is that way set it and throw on the harmonic balancer
https://static.summitracing.com/glob...s/cca-2100.pdf
edelbrock says to rotate it before the damper goes on
https://static.summitracing.com/glob...er-linktim.pdf
Except summit, they pretty much say set the engine at tdc before removing the chain......thats pretty poor instructions if your building a motor
https://static.summitracing.com/glob...s/cca-2100.pdf
edelbrock says to rotate it before the damper goes on
https://static.summitracing.com/glob...er-linktim.pdf
Except summit, they pretty much say set the engine at tdc before removing the chain......thats pretty poor instructions if your building a motor
Last edited by Rescue Rogers; Jul 9, 2020 at 04:48 PM.
Le Mans Master
Joined: Apr 2001
Posts: 5,941
Likes: 281
From: Was New Orleans but swam to Baton Rouge LA
Cruise-In IX Veteran
Because the distributor never lost its relation to the cam. You installed the chain at #6....and when you did, the rotor was pointing to #6 terminal on the cap.....so no issue.
But if you pull the distributor.....and do dot to dot, then point the rotor toward #1 it will be 180 out. It has to be.
Jebby
But if you pull the distributor.....and do dot to dot, then point the rotor toward #1 it will be 180 out. It has to be.
Jebby
wrong again....Like I said, pay attention to the manufacturers instructions. 6 and 12 is #1 tdc for a specific chain, Comp Cams is that way set it and throw on the harmonic balancer
https://static.summitracing.com/glob...s/cca-2100.pdf
edelbrock says to rotate it before the damper goes on
https://static.summitracing.com/glob...er-linktim.pdf
Except summit, they pretty much say set the engine at tdc before removing the chain......thats pretty poor instructions if your building a motor
https://static.summitracing.com/glob...s/cca-2100.pdf
edelbrock says to rotate it before the damper goes on
https://static.summitracing.com/glob...er-linktim.pdf
Except summit, they pretty much say set the engine at tdc before removing the chain......thats pretty poor instructions if your building a motor
"TIMING MARK ALIGNMENT NOTE: Alignment of the timing marks as shown below does not always indicate Top Dead Center (TDC) of the number 1 cylinder on the compression stroke. Many engine families (Chevrolet, Pontiac, etc.) will be at TDC of number 1 on the exhaust stroke and the crankshaft will have to be rotated one full turn before the distributor can be installed and timed"
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,347
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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I now see what Jebby is saying. The edelbrock instructions spell it out perfectly as quoted below.
"TIMING MARK ALIGNMENT NOTE: Alignment of the timing marks as shown below does not always indicate Top Dead Center (TDC) of the number 1 cylinder on the compression stroke. Many engine families (Chevrolet, Pontiac, etc.) will be at TDC of number 1 on the exhaust stroke and the crankshaft will have to be rotated one full turn before the distributor can be installed and timed"
"TIMING MARK ALIGNMENT NOTE: Alignment of the timing marks as shown below does not always indicate Top Dead Center (TDC) of the number 1 cylinder on the compression stroke. Many engine families (Chevrolet, Pontiac, etc.) will be at TDC of number 1 on the exhaust stroke and the crankshaft will have to be rotated one full turn before the distributor can be installed and timed"
This is why I always use Comp Cams chains
Last edited by Rescue Rogers; Jul 9, 2020 at 04:57 PM.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,347
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
really then my motor must be running backwards....pretty ggood to, maybe i should just not read any instructions anymore and be more like you clowns
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Dot to Dot assures your eyeball is seeing exactly what needs to be done on the sprockets without error.
Then you stab the dizzy later. Remember? Thumb over the sparkplug hole?
Clocking the dizzy is the least of your worries after you have everything buttoned up; timing set, timing cover, water-pump, balancer, oil pan, Intake, etc.
One tooth off with the chain and everything comes back off.
Then you stab the dizzy later. Remember? Thumb over the sparkplug hole?
Clocking the dizzy is the least of your worries after you have everything buttoned up; timing set, timing cover, water-pump, balancer, oil pan, Intake, etc.
One tooth off with the chain and everything comes back off.
Last edited by HeadsU.P.; Jul 9, 2020 at 08:36 PM.