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I have a mild cam in a 289 per the builder. He's not sure which cam was chosen, so that's all I have to work with, lol. I'm very familiar with timing engine and have never had a problem. I let the car to 12* and let it warm up. I set the advance dial indicator to 36* and revved the car to 3200 rpm (blocked off vaccuum advance on the carb side). Set the timing to 0, but when I checked back to idle timing it was at 0*. I have a spectre distributor (old distributor cap had a crack in it, so warranty return.) It's a harbor freight timing light, so maybe it **** the bed on me. The last distributor landed somewhere around 12-16* of timing with 36* total. At 12-16* idle this distributor is way past the 40* mark on the balancer.
 

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If you want to optimize performance, start at 6°BTDC, and drive the car. At low rpm, but heavy throttle, if you don't get ping, advance the timing 2° and try again. When you get ping, back off the timing 2°.

For best performance, send the distributor to Dan to have the advance curves set to match your cam and drivetrain.
 
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Why did you set the timing back to 0*? If the total advance is 36* with the initial set at 12* then I don't see a problem.
 

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If you want to optimize performance, start at 6°BTDC, and drive the car. At low rpm, but heavy throttle, if you don't get ping, advance the timing 2° and try again. When you get ping, back off the timing 2°.

For best performance, send the distributor to Dan to have the advance curves set to match your cam and drivetrain.
In case the OP or anyone else didn't know who Dan is

also of note is this place
 

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The last distributor landed somewhere around 12-16* of timing with 36* total. At 12-16* idle this distributor is way past the 40* mark on the balancer.
Not all distributors are created equal. Under the breaker plate you'll see something similar to this -
747384


Sounds like your current distributor is set up with the reluctor plate using an 18L slot (18 deg. x 2 = 36 deg at the crank. If you want less mechanical advance you can tear into the distributor and move to a smaller numbered slot, such as 15L or 13L if it's not already on the smaller slot.
 

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Not all distributors are created equal. Under the breaker plate you'll see something similar to this -
View attachment 747384

Sounds like your current distributor is set up with the reluctor plate using an 18L slot (18 deg. x 2 = 36 deg at the crank. If you want less mechanical advance you can tear into the distributor and move to a smaller numbered slot, such as 15L or 13L if it's not already on the smaller slot.
Yes, here you can limit the timing advance. In case you don't find a smaller slot you can weld the slot at the boot and use a Dremel to open it up again until you reach the value you are looking for. I did it recently to reduce the timing for my GT 40 P heads. If you want to do this I can give you the length of the slot.
 

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Discussion Starter #7
Thanks guys really appreciate the advice. It was a bad distributor. 2 in a row from specter with broken caps....
 
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