Normal range of my Mallory distributor is 10° to 28°, ± 2 to 3 depending on how it's setup.

With my Link Fuel Injection and Ignition controller, I am supposed to "lock" the distributor so that it no longer has any advance since the ECU now controls it.

The distributor is "locked" at full advance.

The problem I seem to be having is that I believe I am getting some spark scatter at the lowest setting due to the rotor armature being too far from the HT lead in the cap, and only at the lowest degree setting of 10°, I can move the distirbutor up to about 13° and it runs better but that is getting too high for easy starting.

I've repositioned the LED inside the Mallory, but with no luck....


So, I started to think, why not just keep the mechanical advance working?? Sure it'll move back and forth but the ECU will be sending the signal of when to fire and it should be fine....

Hope that made some sense

Can you lock the mechanical advance in a different spot? You can check the indexing of the rotor if you drill a hole in the cap near the #1 tower and use a timing light to see where the rotor is when it fires.

And no, please don't use both advances at the same time. It will make proper electronic curve settings too confusing to work with.



Andrew

I would lock it at 0 rather than full advance. Also, try using a rotor with a wider tip. Take a look at the rotor in a 944. It has a broad tip to accomodate the electronic advance.

Or just dump the dizzy and run DIS.

thats what i was thinking, lock it at 0 instead of full advance. Then it adjusts the advance from there up.

You may still get some spark scatter near the top of the advance curve. But I think that with the rotor moving faster when you hit the top of the advance curve it will be attenuated.

I plan on trying to lock it at 0° this weekend..the way it is designed I'll have to fab something to hold it...not that big of deal.

I did make a new and wider tip (from a solid brass door hinge of all things ) didn't seem to help as much....I don't know, there could be other issues I'm overlooking with the darn thing

If I don't have any luck this weekend, I'm sending the ECU, the MSD and dizzy down to So-Cal to let them put it on thier test bench.....who knows, maybe I fried something without knowing it

Making a wider tip may not help things, unless you know what's going on. You may only need to make it wider in one direction, you could get cross firing if you widen it where you shouldn't. I'd say take some careful measurements and find out where the rotor is pointing at the time it needs to fire. If it isn't right, re-index the cap so it's right.

Mike

The problem is rotor phasing. I think you should lock it at about 10-12 deg advance. 964 and 993 ran both mechanical and electronic advance, but why bother if you just run the electronic you can set it with your laptop anywhere you want.

QUOTE (bondo @ Jul 8 2005, 12:29 PM)

Making a wider tip may not help things, unless you know what's going on. You may only need to make it wider in one direction, you could get cross firing if you widen it where you shouldn't. I'd say take some careful measurements and find out where the rotor is pointing at the time it needs to fire. If it isn't right, re-index the cap so it's right.

That's where drilling the hole in the cap and using the timing light would help.

Andrew

I don't think I made that terribly clear. Lock the advance mechanism at full retard. Set the static timing at 12 deg adv. Tell the computer that the dizzy is at 12 dg adv, then set the timing at 6 deg at idle or whatever with the computer.