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cuedog10

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I have a 1972 Mach 1 with a 351 Cleveland motor. I installed a 2 wire hei distributor. Took out the stock distributor and the coil. I wired a dedicated 12 volt wire to the bat. side of the unit and the tach led to the other side. It will not start or even backfire. Is there something else I need to disconnect? Even though the unit is new could it be bad? I really need some help here.   Thanks in advance.

 

73pony

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I am a little confused on how you wired this. You should have used your existing trigger wire to a relay and then the 12v from the relay to the distributor.

 

turtle5353

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Throw away the Chebby stuff and install a duraspark dizzy and box. I just hate the looks of a hei on a ford. But is does sound like you have it wired incorrectly.

 

cuedog10

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The hei instructions were clear to run a 12 volt wire that is hot when you turn the key on to the battery side of the dist. and tach wire to the other side of the dist. It says nothing about a relay or a trigger wire.

 

73pony

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OK. Let me see if I can be more clear with some Ford Specific Instructions.

Your original coil wire has a resistor in it dropping the voltage down from 12 volts to avoid pitting the original points. The HEI needs the full 12 volts.

Here are two ways to wire this. I am running an HEI style distributor.

Option 1 is to bypass the resistor in the pink wire under the dash and use that to supply voltage to the HEI (not my suggestion as I don't like to cut up factory wiring).

Option 2 install a relay, use the original coil wire as the trigger for the relay, supply 12v to the relay and the output to the distributor. (this is how I wired mine and works flawlessly)

Where did you get the 12v source from that you used? You need to have voltage when the key is on but also when it is cranking.

 
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cuedog10

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I will check the voltage. What can I do about the tach/ Thanks

 

midlife

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Tach output is a pink resistor wire (well, red/green on 7123's). It goes to the connector on the back of the fuse box, where it joins with the headlight harness to a red/green wire that goes to the positive side of the coil. The Ford tach MUST be used in-line between the ignition and the coil, but you can replace the resistor wire with a standard wire (not easy to do, especially in the car itself---best to remove the underdash harness and work on it on a bench).

 
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While I'm NO expert at anything, why the heck do people put this junk in FORD motors? A properly rebuilt and curved factory distributor with a Pertronix Ignitor II module and a matching Flamethrower coil OR a Duraspark set up for your motor configuration, is all anybody needs unless it's a drag car and highly tuned. Not only that, but if a factory air cleaner or ram air is used, HEI or MSD will not fit and IMO, look stupid.

A year or so back, a friend of mine who has restored or rebuilt 7 Mustangs (Mach1's) called me to come look at his most recent project. He had bought (for some unexplained reason) a HEI unit off e-Bay, but when he put it in it would not start and when it did fire, it backfired something fierce. The box stated for Ford 351C, so he just dropped it in. When I pulled it out, low and behold the wrong drive gear was on it, likely a 302 if Ford at all. Chinese junk was what it was. I re-installed the factory distributor and timed it as best as possible without rebuilding and altering the slot plate and adjusting the springs and tension. It ran well enough for him to sell the car, which is all he wanted to do anyway.

Just my thoughts on the subject, do as you feel is right for you.

Geoff.

 

Don C

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DuraSpark is one of the best electronic ignitions out there, that doesn't require a computer. Easily tuneable, low cost, and parts are readily available at any auto parts store. And, with the right box, it can be set up for retard on starting, a great feature for performance engines with high compression and initial advance. MSD based their box on the DuraSpark, not HEI. So much for the myth that HEI is supposed to be something special (not just ugly).

 

Tnfastbk

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While I'm NO expert at anything, why the heck do people put this junk in FORD motors? A properly rebuilt and curved factory distributor with a Pertronix Ignitor II module and a matching Flamethrower coil OR a Duraspark set up for your motor configuration, is all anybody needs unless it's a drag car and highly tuned. Not only that, but if a factory air cleaner or ram air is used, HEI or MSD will not fit and IMO, look stupid.

A year or so back, a friend of mine who has restored or rebuilt 7 Mustangs (Mach1's) called me to come look at his most recent project. He had bought (for some unexplained reason) a HEI unit off e-Bay, but when he put it in it would not start and when it did fire, it backfired something fierce. The box stated for Ford 351C, so he just dropped it in. When I pulled it out, low and behold the wrong drive gear was on it, likely a 302 if Ford at all. Chinese junk was what it was. I re-installed the factory distributor and timed it as best as possible without rebuilding and altering the slot plate and adjusting the springs and tension. It ran well enough for him to sell the car, which is all he wanted to do anyway.

Just my thoughts on the subject, do as you feel is right for you.

Geoff.
Not only that, but if a factory air cleaner or ram air is used, HEI or MSD will not fit and IMO, look stupid.

 


Well I guess I like the "STUPID" look also if you look at the last picture with a little thought stock ram air filter assemble will work. The first few are mine and the last one is my uncles.









 

73pony

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I guess I like stupid too. Would not swap out my DUI (HEI) for any 1970's era crap. Car never ran better before I put this distributor in no matter what I did.

 
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While I'm NO expert at anything, why the heck do people put this junk in FORD motors? A properly rebuilt and curved factory distributor with a Pertronix Ignitor II module and a matching Flamethrower coil OR a Duraspark set up for your motor configuration, is all anybody needs unless it's a drag car and highly tuned. Not only that, but if a factory air cleaner or ram air is used, HEI or MSD will not fit and IMO, look stupid.

A year or so back, a friend of mine who has restored or rebuilt 7 Mustangs (Mach1's) called me to come look at his most recent project. He had bought (for some unexplained reason) a HEI unit off e-Bay, but when he put it in it would not start and when it did fire, it backfired something fierce. The box stated for Ford 351C, so he just dropped it in. When I pulled it out, low and behold the wrong drive gear was on it, likely a 302 if Ford at all. Chinese junk was what it was. I re-installed the factory distributor and timed it as best as possible without rebuilding and altering the slot plate and adjusting the springs and tension. It ran well enough for him to sell the car, which is all he wanted to do anyway.

Just my thoughts on the subject, do as you feel is right for you.

Geoff.
Not only that, but if a factory air cleaner or ram air is used, HEI or MSD will not fit and IMO, look stupid.

 


Well I guess I like the "STUPID" look also if you look at the last picture with a little thought stock ram air filter assemble will work. The first few are mine and the last one is my uncles.





All a matter of opinion. The distributor you show does appear to be lower than what I've seen, but not all have the ability to rework an air cleaner shell to fit, which I guess you did (or someone did). My personal preference is for a factory look, but I must say that Mach 1 does look nice. Question, why were the shock tower braces not installed? They are structural after all.

Sorry if I offended you or anyone else.

Geoff.

 
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Hemikiller

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While I'm NO expert at anything, why the heck do people put this junk in FORD motors? 
How about instead of tearing him a new ass on his part choices, we stick to the topic of his question?

 

73pony

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While I'm NO expert at anything, why the heck do people put this junk in FORD motors? 
How about instead of tearing him a new ass on his part choices, we stick to the topic of his question?
Thank you!

 

Tnfastbk

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Sorry if I offended you or anyone else.

Geoff.

Not offended one bit. Just pointing out there are many "opinions" of what works for each. If you look in the picture with the show board they are braces installed. No they are not stock either but work very well.



 

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