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Ever since I had my new dist. installed my mech.can't get my car to stop pinging.....First he moved the timing up to 14 then that made it worse then he backed her down as low as 8 deg. n it still pings when I floor it....Also my temps have slightley increased since we changed dist....Were she would never get over 200 she now sneaks up to 220/225......Please help...Spring is around the corner...Thanx...Jerrylee///
 

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This might be silly and obvious, but could it be the octane of fuel you are using?
 

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Discussion Starter #3
Ping...

I doubt it because even though I have only been on the road since Sept. I have been using Mobil super for the most part..........Jerrylee///
 

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Try filling up the next tank with lower octane. My car runs much better on 89 than it does on 93.
 

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To set up your distributor properly you have to do the following. Don't worry about the initial timing. Open the cap and remove the springs that hold the weights in the distributor. Then close the cap up again, disconnect and plug the vacuum advance, loosen the distributor locking nut and start the car. Rev the engine to about 2500~3000 rpm and set the timing at 36 degrees without the weights. This will give you your max timing. Shut the engine down and reinstall the springs. Make sure the springs are strong enough that they don't start to advance the timing until about 1200 rpm. When you start the car you will see where your initial timing should be. If your distributor gives you 20 degrees of mechanical advance your timing would be at 16 degrees (16 degrees initial plus 20 degrees mechanical advance gives you 36 degrees maximum advance). You can vary this by setting the max between a range of 34 to 36 degrees depending on what runs best. Now that you have your max and initial advance set you can vary the springs so that they advance or retard faster or slower. The mechanical advance should all be in by 3000 rpm. You should then check the vacuum cannister. Many canisters will give you 20 degrees additional advance which is way too much for this distributor curve. You can read the number of degrees on the mounting arm of the vacuum canister under the cap. If your vacuum advance is higher than about 12 degrees you should change it our to one that is about 10 to 12 degrees max. This will give you 46 to 48 degrees mechanical and vacuum advance combined which should be just about right. Fforget about the adjustable vacuum canisters. They're junk and don't really control the maximum amount of advance, just the speed which the canister advance the timing. Hope this helps.

 

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To set up your distributor properly you have to do the following. Don't worry about the initial timing. Open the cap and remove the springs that hold the weights in the distributor. Then close the cap up again, disconnect and plug the vacuum advance, loosen the distributor locking nut and start the car. Rev the engine to about 2500~3000 rpm and set the timing at 36 degrees without the weights. This will give you your max timing. Shut the engine down and reinstall the springs. Make sure the springs are strong enough that they don't start to advance the timing until about 1200 rpm. When you start the car you will see where your initial timing should be. If your distributor gives you 20 degrees of mechanical advance your timing would be at 16 degrees (16 degrees initial plus 20 degrees mechanical advance gives you 36 degrees maximum advance). You can vary this by setting the max between a range of 34 to 36 degrees depending on what runs best. Now that you have your max and initial advance set you can vary the springs so that they advance or retard faster or slower. The mechanical advance should all be in by 3000 rpm. You should then check the vacuum cannister. Many canisters will give you 20 degrees additional advance which is way too much for this distributor curve. You can read the number of degrees on the mounting arm of the vacuum canister under the cap. If your vacuum advance is higher than about 12 degrees you should change it our to one that is about 10 to 12 degrees max. This will give you 46 to 48 degrees mechanical and vacuum advance combined which should be just about right. Fforget about the adjustable vacuum canisters. They're junk and don't really control the maximum amount of advance, just the speed which the canister advance the timing. Hope this helps.

:agree: Perfect. Hei I use the two gold springs from Mr. Gasket. Black and silver for conventional.
 

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A little more information...the subject distributor is an MSD 8572 which has an adjustable mechanical advance limit, with 28, 25, 21 and 18 degree choices.

Jerrylee needs to determine which advance limit bushing is installed. If the 28 degree bushing is in and he chooses to be conservative with the total and uses 34, his initial would only be 6 degrees, which wouldn't be too hot off the line.

Just for the record...Crane makes an adjustable vacuum canister which also has a separate mechanical stop that limits the total amount of advance. It is not easily adjusted, not like the vacuum trip point.
 

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He could have it a tooth off also.
 

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A little more information...the subject distributor is an MSD 8572 which has an adjustable mechanical advance limit, with 28, 25, 21 and 18 degree choices.

Jerrylee needs to determine which advance limit bushing is installed. If the 28 degree bushing is in and he chooses to be conservative with the total and uses 34, his initial would only be 6 degrees, which wouldn't be too hot off the line.

Just for the record...Crane makes an adjustable vacuum canister which also has a separate mechanical stop that limits the total amount of advance. It is not easily adjusted, not like the vacuum trip point.
Adjustable vacuum advances are worthless. IMHO
 
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