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Discussion Starter #1
I have been trying to use the Duraspark distributor in my 289 with a GM HEI ignition module. The problem we have been running into though is that as soon as we hook up the vacuum advance the engine dies, we are running the engine at 6 degrees BTC and when we tried it at TDC it ran better but still died after a couple seconds (less then 30). Has anybody else had this problem?

We have been using the full vacuum port on the carb. When we tried the ported vacuum (edelbrock 1406 600CFM 4BBL) it pops and backfires off idle.

Possible issues we have looked at so far include
too much vacuum advance (i tried to manually create vacuum by sucking on the vacuum line while it was running also, ANY vacuum/advance and it dies)
making sure everything is grounded (does the pickup coil plate need to be grounded?)
different vacuum advance (does ford make them with different amounts of advance? 14 degrees vs 16?)


The other thing we are thinking it could be is that somebody GAVE me the distributor and there may be a problem with the pickup coil.

The tech article I used for information can be found over on the fordsix.com page at
http://fordsix.com/tech/duraspark.htm

Any input would be appreciated.
ron
 

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sounds like the vacuum can...

the pickup can be tested with a multimeter......resistance between the purple and orange wires should be around 400 ohms if memory serves me correctly....

if you hook the multimeter between the black and either the purple OR the orange, it should read MUCH higher than that (upwards of 10,000 ohms)...if not, it's shorted to ground.

if it's bad, I'd go with a napa or ford replacement....
 

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Your Mustang is telling you to get rid of that foul module...hehe just kidding...

Since the HEI module is only $10, try a replacement.

Or wire in a Ford Duraspark II module.

Or wire in an MSD module.

Or how about a Chrysler module.
 
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I tried a different dist and got the same results, it works great (with ported vacuum) when accelerating, but pops and backfires like mad when just cruising/idleing along the highway. I tried a full ford duraspark distributor setup also but I didnt get any spark from the coil (I tested the coil separately and it works) I even tried a different box with it. I pulled the dist and box from a '77 grenada. And to the best of my knowledge my vacuum canister is not working/hooked up (I wasn't working on that till later this summer when I rebuild the heater/AC box) I thought the vacuum can was only used for the heater controls and brake booster (if I had one)?

thanks
ron
 
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