Mallory dizzy, anyone know the OD of one?, need to print a 720° timing disc Options

[Mueller]

Looking for the outside diameter of a Mallory distributor.

Thanks

[lapuwali]

You trying EDIS again?

[Mueller]

QUOTE (lapuwali @ Nov 4 2005, 12:20 PM)

You trying EDIS again?

no, this is for getting the phasing correct using the Mallory and the Link.

I "really" think this is where I screwed up and it has nothing to do with incorrect advance curves. I can program the advance curve to mimic the stock dizzy or the Mallory/MSD curve.

I know I can print out a 360° and divide by 2, but knowing the diameter will help printing out a wheel that is not too big or too small.....

I cannot use the Mallory as a stand alone ignition right now, I got rid of the springs a few months ago....no stock dizzy that is in working order....

[lapuwali]

I have a working Mallory sitting on the 1.7 that's sitting on the floor you can borrow...The 2.2 has a mighty 009 on it. (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

[airsix]

Mike,
In case what I was saying yesterday on the phone didn't make sense (I'm terrible at explaining mechanical things), here's the method I used for setting mine before I went to a crank mounted sensor. You'll notice this is similar to how you would "rough in" contact points. I've amended this procedure slightly from what I said on the phone because I thought of something else...

I think you're headed down the wrong path measuring anything off the distributor possition. I'm confident that if you follow this procedure you will have your sensor indexed correctly in very short order.

1. Turn your crankshaft by hand to 20 degrees AFTER TDC using impeller timing marks as reference.
2. Rotate distributor body until rotor is perfectly alligned with the distributor cap cyl-1 post.
3. Lock down distributor in this possition and never move it again. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)
Steps 1,2,3 insure that under running conditions the cap-to-rotor allignment is optimal.
4. Turn the crankshaft to the angle at which the ECU crank possition signal should be triggered (in this case -10 degrees TDC) using the marks on the impeller as a visual guide.
5. Hook your optical sensor output signal to a 12v LED (temporarily). Verify that the LED will light when sensor shutter is open and turns off when sensor window is obstructed (Remember, DON'T move the crank OR the distributor body!).
6. Install sensor in distributor and move it counter-clockwise (anti-clockwise for our European and Australian friends) toward the closest shutter slot.
7. As the sensor is moved over the shutter window (slot), stop at the instant the LED turns on.
8. Lock down the sensor in this possition.
9. Move crank back a few degrees and then move forward again. LED should light just as you get to 10 degrees BTDC.

Your sensor is now properly indexed to trigger at 10 degrees BTDC. Start your engine. (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif) (After installing rotor and cap of course. Oh, and after you take off the LED and hook the sensor output back up to the ECU.).

I think you should use this method rather than trying to use a degree wheel on the distributor because:

• You want 10 degrees BTDC measured off the crank, not distributor, which can be moved.
  
• In this application the distributor possition should be a function of lining up the rotor and cap for optimal spark transfer, nothing more. To change sensor-timing move the sensor or the shutter-wheel, not distributor body.
  

I hope this is helpful. The above method works better than half-dozen other things I tried before I got that technique figured out. I hope this saves you some frustration.

-Ben M.