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Old Mar 9, 2016 | 03:28 PM
  #21  
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Default Recurved

Originally Posted by 1972LT1
I just checked with previous owner, he said he had the distributor re-curved but doesn't know specs.
Remove one of the distributor springs. Set the dial on your timing light to 36 degrees. Start the engine and hold it at about 2,500 RPM and after slightly loosening the distributor hold down turn it so the line on the spinning damper lines up with the zero on the timing tab, tighten the hold down and reinstall the spring you removed.

Last edited by MelWff; Mar 9, 2016 at 04:44 PM.
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Old Mar 9, 2016 | 03:33 PM
  #22  
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Originally Posted by SH-60B
The notch in the balancer should line up with the 4* BTDC mark on the timing tab. This is at 900 rpm, vacuum disconnected and plugged.
Ok I understand that. When I rev it up am I still going to use the 4* BTC mark then use dial back on light to see where the timing is set at higher rpm?
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Old Mar 9, 2016 | 04:38 PM
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Originally Posted by MelWff
Remove one of the distributor springs. Set the dial on your timing light to 36 degrees. Start the engine and hold it at about 2,500 RPM and after slightly loosening the distributor hold down turn it so the line on the spinning damper lines up with the zero on the timing tab, tigthen the hold down and reinstall the spring you removed.
Okay Mel, I will do that tonight thanks
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Old Mar 10, 2016 | 06:07 AM
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Originally Posted by 1972LT1
Ok I understand that. When I rev it up am I still going to use the 4* BTC mark then use dial back on light to see where the timing is set at higher rpm?
I'll try this again, my previous post was deleted. Reference the 0* mark on the timing tab, then dial the light back to find the amount of advance.
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Old Mar 10, 2016 | 10:53 AM
  #25  
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Originally Posted by SH-60B
I'll try this again, my previous post was deleted. Reference the 0* mark on the timing tab, then dial the light back to find the amount of advance.
That's exactly what I did. On original post/question I only saw 36* with vacuum hooked up and the 4* ATDC.
Am I supposed to be manully adding initial timing to the reading I see on my back dial? I thought I adjust light to zero mark & that is a direct read of total timing.
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Old Mar 10, 2016 | 11:38 AM
  #26  
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Have you read Lar's paper on timing ? If not, search the forum. It is very good.
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Old Mar 10, 2016 | 11:44 AM
  #27  
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Originally Posted by 1972LT1
That's exactly what I did. On original post/question I only saw 36* with vacuum hooked up and the 4* ATDC.
Am I supposed to be manully adding initial timing to the reading I see on my back dial? I thought I adjust light to zero mark & that is a direct read of total timing.
1) Set dial to 36
2) 0 becomes your timing pointer...adjust to zero for 36 degrees.
3) Set dial to 0
4) Set idle to 900...Record the number on the tab...(I.E. "4" or "6") this is your initial.
5) Post your findings

Jebby
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Old Mar 10, 2016 | 11:47 AM
  #28  
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Default Timing

Originally Posted by 1972LT1
That's exactly what I did. On original post/question I only saw 36* with vacuum hooked up and the 4* ATDC.
Am I supposed to be manully adding initial timing to the reading I see on my back dial? I thought I adjust light to zero mark & that is a direct read of total timing.
First you dont do this with the vacuum connected. Second if you set the light to zero and increase the engine speed the only way you will be able to read the total timing is if you have a non-factory damper that has degree marks going to at least 36 BTDC. That is why you set the dial to 36 and increase the rpm with a goal of seeing the mark line up with the zero on the timing tab thus eliminating the need for a degreed damper.
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Old Mar 10, 2016 | 11:47 AM
  #29  
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Originally Posted by 1972LT1
Okay Mel, I will do that tonight thanks
Well, my plans last night was not some one else's plan. I'm sure most of us know what I mean.
Out of curiosity, why is one spring removed and if they are visibly different springs would the heavier or lighter spring be removed?
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Old Mar 10, 2016 | 02:23 PM
  #30  
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removing the spring permits the total timing to come in earlier rpm wise so you dont have rev the engine as high to determine what that total number is. If different remove the heavier spring.
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