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Discussion Starter #1
cant seem to get any total advance,changed the springs today,still nothing.but i noticed that the weights are snapping back with the rotor off but when i put the rotor on everything seems to bind up and the rotor wont snap back...am i missing something obvious?? help!
 

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cant seem to get any total advance,changed the springs today,still nothing.but i noticed that the weights are snapping back with the rotor off but when i put the rotor on everything seems to bind up and the rotor wont snap back...am i missing something obvious?? help!
Get a new rotor!! That one (for whatever reason) is tightening down on top of the weights instead of OVER them.:yes:
 

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Discussion Starter #3
okay have that problem solved with a different cap..next question..if i have my light set at 0 it shows around 16 deg at idle,but if i use the dial and roll it back it shows closer to twenty on the dial before reading 0 on the timing tab..so what do i believe
 

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I'd tend to believe your dial, those marks on the tab are hardly an accurate indicator. You really shouldn't be so concerned with what it is in reality anyway, you just need a reference to go from. For instance if you read 18° with whatever, it's a reference. You then can go ahead or behind whatever your motor needs as you drive and test things.
 

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okay have that problem solved with a different cap..next question..if i have my light set at 0 it shows around 16 deg at idle,but if i use the dial and roll it back it shows closer to twenty on the dial before reading 0 on the timing tab..so what do i believe
Not cap.....ROTOR..:D

Get some timing tape or use a degree wheel and a piston stop to find TRUE TDC and mark your own degree increments on the balancer. White liquid paper seems to REALLY jump out there when looking with the light!! Make sure to extend the TDC mark well into the center of the balancer's hub and or crank pulley that way if the outer ring ever "Slips" you'll know.
Doing this will allow you to check the accuracy of your light as well.:yes:

You can also check it against another timing light. I have 3 so it's easy for me.:devil::yes: I still ALWAYS find true TDC and mark the balancer as described above. :yes: Just safe practice..

I don't use or recommend using the timing "Tabs" with several teeth. If I come across one I usually use a set of tip snips to trim it to a point for TDC ONLY. It just make the visual that much easier!!
 

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Discussion Starter #7
sorry i meant rotor..no it's not digital and ya i guess i need to find true tdc,,when we put the motor together we lined up the balancer with 0 on the tab but i guess the tape is the way to go
 

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sorry i meant rotor..no it's not digital and ya i guess i need to find true tdc,,when we put the motor together we lined up the balancer with 0 on the tab but i guess the tape is the way to go
Lined up the balancer with the zero? That doesn't mean anything if you don't know where the mark is relative to the #1 piston!

We have timing tape info in "Best of" and how to mark your balancer, and how to find true TDC, how to limit advance. These are basic skills, people. You shouldn't be messing with timing curves if you don't know how to do simple things like verifying true TDC when you are assembling the engine.

I disagree that the dial is more accurate than the tab...if the tab is calibrated properly and the light circuitry is working properly. It depends on the light. Some cheap lights are notoriously bad. A good timing light and a vacuum gauge are essential tuning tools.
 

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I still don't see how finding true absolute TDC is going to help with setting timing for power. He's setting timing not degreeing advancing/retarding a cam. It's good to know how to do it but isn't going to solve anything here.

Choose some springs for the advance mechanism that provide a sweep that starts about 1000 RPM and is at full advance about 3000 RPM. Check your initial, check your total. Subtract the two numbers, that's the sweep range. Check what RPM full advance happens. Who cares what the numbers are or should be dead nutz, they're nothing more than a reference. So instead of 12° initial he reads 14° instead of 32° total he reads 34° what's the big deal. Keep advancing it until ping is heard and then back it off 2° or so.

You can stick the tape on the balancer to get a sight of everything and verify the sweep range. But making sure the zero mark is absoulutely TDC isn't that critical for twisting a dizzy and finding the most power. Only unless you want to know EXACTLY what your initial and total is. How is that going to help, I guess it can give you a warm fuzzy. It isn't going to help find all the power the motor can make.

Hell I'm going out now and re-write all my marks adding 7 to the numbers on the tape. Guess my motor won't run right then huh? Of course it will. So instead of 12° initial I read 19° instead of 32° total I read 39° what's the difference I still have a 20° sweep and it's still timed right for my combo. I guess the difference would be I would lose sleep knowing the numbers arent painted on dead nutz accurate. Instead of 0 being TDC it's 7° oh the horror of it all.
 

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Discussion Starter #10
thats what i like to hear,unfortunatley i don't have keith dorton as my neighbor..lol and big al lives a couple of thousand miles away so he's out of the question..i was always told by my elders turn her till she pings and back er off..i'm not trying to run 10 seconds,i just want to lay some rubber.. thanks for everybody's help
 

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cranker, no disrespect here, you really should learn how to it correctly in spite of taking advice from those that have learned through trial and error. Next time you have the motor out, set up the balancer and pointer to true TDC with a piston stop or dial indicator, there's literally hundreds of articles on the web that expalian how to do it.

Yeah, you can get motor to run pretty decently without all that, but knowing the how's and why's things are happening is a little more comforting than just twisting the dizzy body until she runs good.

Just food for thought. :cool:
 

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I still don't see how finding true absolute TDC is going to help with setting timing for power. He's setting timing not degreeing advancing/retarding a cam. It's good to know how to do it but isn't going to solve anything here.

Choose some springs for the advance mechanism that provide a sweep that starts about 1000 RPM and is at full advance about 3000 RPM. Check your initial, check your total. Subtract the two numbers, that's the sweep range. Check what RPM full advance happens. Who cares what the numbers are or should be dead nutz, they're nothing more than a reference. So instead of 12° initial he reads 14° instead of 32° total he reads 34° what's the big deal. Keep advancing it until ping is heard and then back it off 2° or so.
Bad advice and an "old myth" since pinging threshold isn't an indication of anything performance related and peak power may not be "just before" audible detonation. ~Paul W.

You can stick the tape on the balancer to get a sight of everything and verify the sweep range. But making sure the zero mark is absoulutely TDC isn't that critical for twisting a dizzy and finding the most power. Only unless you want to know EXACTLY what your initial and total is. How is that going to help, I guess it can give you a warm fuzzy. It isn't going to help find all the power the motor can make.
Timing is relative to TDC. If your reference to TDC is wrong your timing will be wrong also. ~Paul W.

Hell I'm going out now and re-write all my marks adding 7 to the numbers on the tape. Guess my motor won't run right then huh? Of course it will. So instead of 12° initial I read 19° instead of 32° total I read 39° what's the difference I still have a 20° sweep and it's still timed right for my combo. I guess the difference would be I would lose sleep knowing the numbers arent painted on dead nutz accurate. Instead of 0 being TDC it's 7° oh the horror of it all. If the balancer outer ring has slipped the reading won't be accurate and could be off by a significant amount. It could look like 38 degrees but actually be 52. ~Paul W.
I put my comments in blue italics. Read the thread on vacuum gauge timing in "Best of" for more info on why you are incorrect. Your methods are based on grossly incorrect assumptions about best timing for maximum performance.
 

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I still don't see how finding true absolute TDC is going to help with setting timing for power. He's setting timing not degreeing advancing/retarding a cam. It's good to know how to do it but isn't going to solve anything here.

Choose some springs for the advance mechanism that provide a sweep that starts about 1000 RPM and is at full advance about 3000 RPM. Check your initial, check your total. Subtract the two numbers, that's the sweep range. Check what RPM full advance happens. Who cares what the numbers are or should be dead nutz, they're nothing more than a reference. So instead of 12° initial he reads 14° instead of 32° total he reads 34° what's the big deal. Keep advancing it until ping is heard and then back it off 2° or so.

You can stick the tape on the balancer to get a sight of everything and verify the sweep range. But making sure the zero mark is absoulutely TDC isn't that critical for twisting a dizzy and finding the most power. Only unless you want to know EXACTLY what your initial and total is. How is that going to help, I guess it can give you a warm fuzzy. It isn't going to help find all the power the motor can make.

Hell I'm going out now and re-write all my marks adding 7 to the numbers on the tape. Guess my motor won't run right then huh? Of course it will. So instead of 12° initial I read 19° instead of 32° total I read 39° what's the difference I still have a 20° sweep and it's still timed right for my combo. I guess the difference would be I would lose sleep knowing the numbers arent painted on dead nutz accurate. Instead of 0 being TDC it's 7° oh the horror of it all.
I know what you mean but when I don't know what balancer he's got or what timing marks, it's just easier to MAKE sure. What does it take....an extra 10 minutes?:rolleyes:

Let's say someone gave him a late model balancer that's supposed to be run with the timing marks straight up (@ 12 o'clock) and he's got the timing pointer that sets at 2 0'clock.....How far off is he?:eek:

Or (Like we've seen here in the past) he's using the wrong plugs (too short of a reach) and is having to run 50 degrees of total timing to get DECENT performance?

in either case, without KNOWING where -0- is he'll never know......It'll just be a reference....Who cares what the number is right?

And as for marking true -0- all the way into the center hub while you're at it......A year down the road you do a tune-up. 16 degrees initial isn't what it used to be because the outer ring slipped.....How many circles are you going to run while you're trying to figure out WHY the best performance is NOW at 22 or 5 degrees initial?? With a reference mark that was done a YEAR ago, a simple glance got you your answer....

There's doing things RIGHT and then there's just doing enough to get by.... I know the difference and I choose (99% of the time) to do it right the first time and not even run the chance of having to do it over or chase my tale later.:yes:
 

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You're really missing the point, he isn't that far off to worry about whether it's exactly 16° or 20° pick one and use it as a reference. If you want to explain how fuel and plug heat range affects timing and power be my guest.

What if the numbers were written in Chinese? Would it still be wrong then? OMG NO ZERO MARK WHATEVER WILL I DO. I guess you're just not going to see my point due to indifference. Yes we all know 0 should be TDC but who cares? It's not in this case, maybe it's 4, 4 is still a number from I recall. I don't care if his balancer and pointer is 10° off he can still tune his motor.

If you don't get it you never will. You're stuck on a term, zero. Semantics, it's almost as if you're saying without finding true TDC you can't make a motor run. No one knows on fresh built combo what the initial should be anyway, how does a true 0 mark help you decide that? It doesn't in the least.
 

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You're really missing the point, he isn't that far off to worry about whether it's exactly 16° or 20° pick one and use it as a reference. If you want to explain how fuel and plug heat range affects timing and power be my guest.

What if the numbers were written in Chinese? Would it still be wrong then? OMG NO ZERO MARK WHATEVER WILL I DO. I guess you're just not going to see my point due to indifference. Yes we all know 0 should be TDC but who cares? It's not in this case, maybe it's 4, 4 is still a number from I recall. I don't care if his balancer and pointer is 10° off he can still tune his motor.

If you don't get it you never will. You're stuck on a term, zero. Semantics, it's almost as if you're saying without finding true TDC you can't make a motor run. No one knows on fresh built combo what the initial should be anyway, how does a true 0 mark help you decide that? It doesn't in the least.

So basically you're saying he could be at 30 initial but it might only show 4 on the timing marks add another 20 mechanical and the first time he spins it to 6500 the pistons shatter? I guess the numbers don't mean anything..... I wonder why they even put timing tabs on? I think I'll just toss my timing light in the trash.
 

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ALLT4: Sorry, the minute you said:
"Keep advancing it until ping is heard and then back it off 2° or so
you discredited yourself as an expert.
 

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Here's why:

If you put a degree wheel on a short block and a dial indicator on the piston at TDC, you'll see there is about 15 degrees sweep of crank movement around TDC before the piston/rod has moved far enough to have leverage on the crank throw.

An engine will make the most power when peak cylinder pressure occurs the piston is 12-15 after TDC when the piston is beginning to descend. Before that the piston and rod are near vertical and the force will be transferred as a hit into the bearings. Peak pressure occuring much after that, the piston has descended too far for complete combustion and power wasted.

For peak pressure to occur at the optimum crank angle, it is necessary to initiate combustion, before TDC. Pressure is builds as the flame begins at the spark plug and burns fuel across the chamber. The piston is rising against the increasing pressure causing a loss in torque (negative torque).
This is an acceptable loss because when peak pressure occurs at the right crank angle after TDC, the positive torque is much greater.

Let's choose a particular engine combo that has been proven to make the most power at 38 degrees total timing.

Fill the tank with 87 octane. Twiddle the distributor until it knocks, back it off 2 degrees. Check the timing and it's 33 degrees.
Drain and fill the tank with 110 octane. Twiddle the distributor until it knocks, back it off 2 degrees. Check it with a light. 45 degrees.

If you tune your engine without a timing light and based solely on audible spark knock you are not going to get optimum timing. You may luck out and it may be close, or.... it could be way off, waste power and damage the engine.
 

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So basically you're saying he could be at 30 initial but it might only show 4 on the timing marks add another 20 mechanical and the first time he spins it to 6500 the pistons shatter? I guess the numbers don't mean anything..... I wonder why they even put timing tabs on? I think I'll just toss my timing light in the trash.
Here Bob, maybe this will help you understand what I mean, I doubt it, you're stuck on numbers.



Here’s a scenario that might help explain why you guys think I’m nutz. In the picture is an engine that is making its peak horsepower whatever you want to call it but the marks are 5° off. Joe Bob racer is at the track and “observed” these numbers on his timing tab. Joe Bob figures that his balancer is off, he doesn’t really care how much, what the numbers are, only that he now knows that through testing this curve and numbers perceived have given him his best ET and MPH. Log it and lock it.

For all I would care those numbers could 20° off and still be correct. They’re just numbers, however if the balancer/pointer were that far off I doubt you could still see anything. For argument lets say they were off the other way, 5° retarded. Now you have 10° initial and 30° total, big freakin deal, it still has the best curve and maximum performance. Joe Bob racer at this point might scratch his head and go “by gum I thunk me balancer may be slipping need to recalibrate those TDC marks” Having his TDC pointer off didn’t stop Joe Bob racer from tuning did it?
 

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If the outer ring has slipped, that means the elastomer ("rubber") is no longer bonded to the hub. Even if the outer ring didn't fly off and bonk Joe Bob racer in the head, the outer ring would continue to have a variable timing indication and any subsequent checks would give a different value. You have the classic "my timing doesn't stay put" problem. Since you haven't verified the timing mark represents true TDC, you wouldn't know if the difference in expected timing from observed is due to a slipped hub, balancer timing tab mismatch or slipping distributor, or other stupid mistakes.

Your example of 40 degrees observed really could mean 35 degrees isn't something I would agree with. It presumes whatever discrepancy between correct crank angle and observed crank angle is precisely off.
A slipped balancer outer ring (common problem on old balancers) will continue to slip and rotate to different positions.

But hey, a stop clocked is very accurate twice a day. That doesn't make it an an accurate method of telling time.
 
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