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Author Topic:   Distributor - Mechanical Vacuum or Solid
Dirt Roller

Total posts: 11
posted September 17, 2001 05:53 PM
I am about to put my distributor in and I was wondering what everyone's opinion is about advance. Some people have told me to take it to a shop and have the stock vacuum advance converted to a mechanical style. I have also had people offer to weld the advance where it should be. I am still learning about timing / advance and would like you all to give me some direction. Thank you for the help?


Dirt Newbie

Total posts: 4
posted September 19, 2001 07:52 PM
Take the vacuum advance out, and replace with a dummy type (Performance Distribtors sells these) so that it will lock the advance all the time. (also it just bolts in the bottom of the dist.I think it is just 3 bolts). And depending on what dist. you whether it be an MSD,Perfomance Dist., or just a stock HEI you will have to take all the springs and weights out now if you have an MSD Dist., then it is very simple you just pull the pin out of the gear at the bottom, pull up on the shaft and rotate it 180 degress and put it in the slot that they have provided. Then just install the gear and pin and your done, no welding involved.
Now if you have a stock or PERFORMANCE Dist., Dist., Then you have to take all the weights out and spings, then right in the center of the pivot point (for the weights to move in and out) and you have to weld it. Make sure that you don't get your heat too hot when welding or you could destroy your pickup coil. But also make sure that you weld sticks and you must make sure your surfaces that you are welding are absolutly clean.I Hope that this all helps and maybe I cleared up some of your ?'s.:

[This message has been edited by WILDphil (edited September 19, 2001).]

Dirt Newbie

Total posts: 4
posted September 30, 2001 09:38 PM
Hey guys is it necessary to do all this on the advance?? If you don't hook it up I don't think the advance will work at all--with any distributor--I think... We haven't had any problems with this but maybe we should be doing something else also.. I'll check back for more input.. thanks

Dirt Full Roller

Total posts: 26
posted October 01, 2001 11:22 AM
Good question Wheels. While it is not usually neccesary to remove the vacuum canister some choose to because it is useless weight and can be in the way (especially if you have added ports in the manifold to externally route water from the back of the heads). Something else that is usually done when the canister is "locked down" is "phasing" the distributor, but you can look inside your cap to see if you are out of phase by noting where on the terminals (that the spark plug wires are plugged into) the arc from the rotor is striking (if it is at one edge you should have your dist. re-phased, if it is closer to the center you are good to go).
Good luck
I just read one of the previous posts in this thread so I felt the need to add a little more......

DON'T (I repeat DON'T) lock up your mechanical advance . Have someone who knows what they are doing set up your mechanical advance so that it all comes in by 3000 RPM (requires lighter springs).
A nice touch as well is to have the total Mechanical advance limited to about 18 degrees (a good distributor guy can do this by partially welding up the slots).

Good Luck (and good luck to anyone who has welded up their dist solid when they have to restart their engine)

[This message has been edited by c21 (edited October 01, 2001).]

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