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Discussion Starter #1 (Edited by Moderator)
(mod notes: HEI distributor. Idle too high with vacuum advance connected)

Vacuum is sourced correctly, but idle speed is way too high, should be nearer to 650/700 rpms in park.

You also have too many degrees of vacuum advance, and need to restrict the degrees down to 8/10 crankshaft, easy to do. Send me a real e'mail address I can send pics and I will do so of a limiter you can easily make. This engine likes between 14 and 20 degrees timing at idle speeds of 650/650 rpms.

Does this engine have a higher than stock duration cam, multiple carbs, etc.

The 292 HEI is emissions curved and the vacuum advance isn't restricted, therefore, it needs work to properly time the non-emissions engines. Not that hard to do.
 
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(Mod notes: Advice on setting dwell)

30, NOT 28, NOT 32, NOT 287, not 17...30.

Set the dwell first, then the timing, while making sure the dwell stays steady. After 1,000 miles, reset the dwell...to 30 degrees...because the rubbing block on the points wears into the points cam. Timing should come right back when the dwell is returned to 30 degrees.
 
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(Mod notes:Advice on MSD Billet distributor timing problem)

Read the pickup ohms, should be between 600 and 800 ohms.

Also, check the wires in the black connector
Wire black w/purple stripe, connector term 1
Wire black W/orange stripe, connector term 2

Also, take a look at the magnet under the pickup. The end of the magnet on the pickup coil end should have a Marks-A-Lot line on the end, top to bottom, and on the other end, just past the last holddown nut, NO stripe.

If the magnet is reversed, the timing will misphase 30 to 45 degrees

Same with the wires in the wrong connector holes.

And, NO, the wire connections from the dist to the extension to the ignition box are NOT color matched.
 
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I wouldn't.

Since it has no vacuum advance, lets do a phase test, please.

Check the timing, set it to a known degree, like your 20. Shut the engine down and rotate the balancer to the degree you had on the timing scale, 20 deg/BTDC. Pull the cap off and take a look at the rotor, and just where it is pointing. It should be pointing directly to one of the cap terminals, preferably number 1 or 6 wire. If it is between terminals, or significantly off the term, the pickup is triggering the spark in the wrong place in relation to the terminals in the cap, it would be misphased.

I'd rather see this test done at between 8 and 12 deg/BTDC, but lets see what you come out with, shall we.

Just FYI everybody, a mechanical only dist will always have the rotor pointed to the center of the terminals in the cap when the timing is set to a set degree and checked. A vacuum advance dist will always have the rotor centered on the term in the cap with the vacuum advance half way actuated, as in if the vac is 12 deg, and the initial is 10, the rotor won't align correctly until 17 deg/BTDC.

Just on a whim, you might also just change the coil, even to a used stocker and test the timing. If the coil is defective, it could be causing mis-triggering. Long shot, but worth eliminating as a problem/issue.

I may have to make a few more paint projects about all this stuff, just so others can post them for all to see and hopefully, better understand.
 
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Discussion Starter #5 (Edited by Moderator)
(mod notes: Advice on vacuum advance)

"Timed" is ported vacuum sourcing, and you do not want that.

What you have is a distributor set up by a person that has NO idea as to how to set it up correctly, as the person deleted the load compensation "vacuum advance" device.

The Holley info is erroneous as well, as it only gives findings from a dyno hero, another that has no idea as to how vacuum advance works. When an engine is run on a dyno, the hero dyno operator sees the engine as needing more timing and jetting to make power.

In the real world of driving the vehicle, and not the dyno around the block, dyno timing settings are out to lunch.

Now, to use the vacuum advance correctly,

Recurve the distributor to give 12 degrees initial advance.

Set the mechanical curve for 24 cranksnaft degrees, which will give 36 degrees total. Start the curve at 100 rpms over out of geat idle speed, limit to 2,600 to 2,900 rpms.

Set the vacuum advance pull pin travel at .086 (8 crankshaft degrees) with a stop that allows the pin to pull up from its rest position, to the stop you will make. After this is done, connect the vacuum advance to FULL MANIFOLD VACUUM SOURCING, NOT PORTED. You will now have the mechanical advance curve you want, with the idle timing at the 20 degrees you now have.

And, PLEASE, stay away from that person that doesn't have a clue about how to properly set a vacuum advance up.
 
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