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Resistor bypass

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Old Jan 9, 2022 | 07:27 PM
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Resistor bypass

Just worked out some low voltage ignition bugs. Ending with a resistor bypass and upgraded coil. Now have 12.3 volts at idle going up to about almost 13 at rpm, but now this sucker is hard to start. Doesn't matter hot, cold, warm,. Always have to crank for bit to get er fired up. If going to a hotter spark, is there anything else that needs to be done such as timing change, regap plugs, different plugs, fuel mixture? Just trying to sort this out. Thanks!
 
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Old Jan 9, 2022 | 09:26 PM
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Depending on your ignition system are you sure it's made for 12V ?

Assuming your ignition is good it's probably carburation or maybe timing.
 
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Old Jan 10, 2022 | 08:27 AM
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Ignitor module that's been in for 10 years or so, and a new 1.5 ohm flamethrower coil with new wiring from I terminal, ignition run. Ngk v power plugs gapped at .040, stock dist cap, new batt, and newish plug wires.carb is Holley 500 with regulator set at 5-6 lbs, stock newish fuel pump
 
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Old Jan 10, 2022 | 08:39 AM
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was it hard to start before the work was done, or now hard to start after?
before you try starting, do you see a good stream of gas from the accelerator pump?
if you have bypassed the factory resistor wire and the coil + is always getting a full 12V, there is no need for the I wire from the solenoid.
 
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Old Jan 10, 2022 | 09:26 AM
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Acc pump is good. Carb is 2 months old. Still need to jet it for 8000 ft elevation, but jets are taking forever to ship. Always started good, as soon as starter engaged it would fire no matter the temp or time. I had a resisted msd blaster 2 coil burn out, and horn relay parasitic drain that also came along with dropped ignition voltages. Unplugged horn relay, replaced coil, lifted ignition volts. Just hard starts now
 
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Old Jan 11, 2022 | 12:22 PM
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With the ignition off, temporarily connect a 12 gauge wire directly from the battery + terminal to the coil + terminal, and then try starting the engine.

Connect to the coil + first, and then to the battery +.

Remove the temporary wire immediately after. (remove at battery first.)

Post up the result.
 
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