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-   -   HEI with Ford Duraspark module to retard timing under boost (http://www.hotrodders.com/forum/hei-ford-duraspark-module-retard-timing-under-boost-217639.html)

Augusto 04-01-2012 01:36 PM

HEI with Ford Duraspark module to retard timing under boost
 
I just found out that the white wire in the Duraspark module retards like 6 degrees the timing to help cranking, well if I wire a boost switch that activates at something like 3 psi and wire it to the white wire it will retard the ignition timing and let me run more boost on my supercharged SBC 350.

the question is, can I trigger the duraspark with the HEI reluctor?

I know, since I have done, that the Ford reluctor triggers the HEI module but have never done the other way, I guess it should, shouldn't it?

I've heard that the duraspark can't handle much primary current, can it handel a big yellow Accel coil?

any ideas about the boost switch? I already looked and the buick turbo switch is not available over here.

thanks

LATECH 04-01-2012 01:55 PM

Quote:

Originally Posted by Augusto
I just found out that the white wire in the Duraspark module retards like 6 degrees the timing to help cranking, well if I wire a boost switch that activates at something like 3 psi and wire it to the white wire it will retard the ignition timing and let me run more boost on my supercharged SBC 350.

the question is, can I trigger the duraspark with the HEI reluctor?

I know, since I have done, that the Ford reluctor triggers the HEI module but have never done the other way, I guess it should, shouldn't it?

I've heard that the duraspark can't handle much primary current, can it handel a big yellow Accel coil?

any ideas about the boost switch? I already looked and the buick turbo switch is not available over here.

thanks

You may be able to retard timing with the white wire, but you will need to verify that as the red may be hot also, which may hav an effect or not while running, not sure about that part of the duraspark module.
I do know however that the duraspark keeps the coil on ( grounded) when the engine is not running but the key is on, the coil is allways charging/hot and that can cause coil burnout and kill modules.
The GM HEI module on the other hand turns the Coil - on and off, developing ignition dwell time to fire the coil, keeping it saturated well without over heating it like the duraspark.when the GM HEI is on and the engine is not running the hei doesnt keep the coil grounded, so it wont overheat the coil / module if the key is on and the motor isnt running.
Some of the early 5 pin modules like the HEI/EMR (electronic module retard) use a ground to the 5th pin to retard the timing.

LATECH 04-01-2012 02:02 PM

Oh and the GM pickup should be quite sufficient to trigger the duraspark.
The green on the gm trigger should go to the purple on the duraspark (-)
The white on the gm trigger should go to the orange on the duraspark (+)

Augusto 04-02-2012 10:28 AM

so you think using a GM 5 pin would be a better idea?

do you have a diagram of this module to see which is the 5th pin?

thanks for replying.

LATECH 04-02-2012 06:08 PM

just google it.
GM HEI/EMR ignition module
Tons of stuff will come up. :D

Augusto 04-03-2012 09:47 AM

thanks God for google :D

I did my search and found so far that there are two styles of 5 pin modules, one retards when the 5th pin gets voltage and the other when it's grounded, now I don't know which to use.

I like the idea of sticking to HEI parts, specially because I read that the ford module can't handle big coils.

LATECH 04-03-2012 04:03 PM

you can use the one with the positive feed to retard and hook it to the starter solenoid wire, so when the starter is cranking the module will drop timing to make it easy to start.OR hook it to a WOT switch to retard at full throttle like you were thinking
You could use the ground controlled one by simply using a relay on the same sterter solenoid wire, Or WOT switch, just use terminals 30 and 87 for a ground path instead of power. :D

Augusto 04-05-2012 11:51 AM

thanks, but I still have another question, please tell me what do you think,

I've done some research and seems like the module that I need was meant for Oldsmobile and Pontiac cars that never showed up in this shores, so no luck finding them here, the only 5 pin module available is the one that came in 81 and later Blazer and Pickups with the ESC system which uses a knock sensor and a retard/control box.

Do you think that one would do the same? what kind of input does this 5th pin takes? or is it an output terminal for the ESC box?

I tend to think that the ESC box picks up the signal from the knock sensor then sends a + or - signal to the module in order to retard the timing, but I might be wrong, if this was the case then this module would work for my project same as the Olds module would, I don't know how this system works, could you help me?


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