Is my Thunderbolt V considered HEI?

poconojoe

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I see HEI mentioned sometimes. Does my 2003 carb 4.3L (OM643729) have an HEI distributor?
What exactly is HEI? Does it just describe the distributor or is it also other components?
Just looking to educate myself...
Thanks,
Joe
 

Bt Doctur

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HIE= High ,Energy, Ignition similiar to GM dist with the coil in cap. ThunderBolt is an electronic ign system using a standard coil and Hall effect switch for advancing the timing.
 

Scott Danforth

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No, HEI is an trade name or brand name for an automotive distributor available from 1975-199X on GM vehicles. as BT Doc stated, it stands for High Energy Igniton. (All ignitions are actually high energy as the coils produced 45,000 volts or higher)

it is a coil in cap design that replaced the points ignition.

the TB V is ThunderBolt which was Carl Kiekhaefer's trade name for ignitions at Mercury Marine and the name was carried over to the Mercruiser product. as BT Doc stated, its a complete electronic advance amplifier with rev limiter and knock control that is controlled by a hall-effect trigger and fires a separate coil.

think of the TB V like a marine version of the MSD ignitions that people think their cars need.
 

poconojoe

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HIE= High ,Energy, Ignition similiar to GM dist with the coil in cap. ThunderBolt is an electronic ign system using a standard coil and Hall effect switch for advancing the timing.

So my TB V is not HEI...correct?
I do recall from the classic automotive world the HEI distributor replacing a points system. It was an easy one wire hookup if I recall correctly.
 

poconojoe

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No, HEI is an trade name or brand name for an automotive distributor available from 1975-199X on GM vehicles. as BT Doc stated, it stands for High Energy Igniton. (All ignitions are actually high energy as the coils produced 45,000 volts or higher)

it is a coil in cap design that replaced the points ignition.

the TB V is ThunderBolt which was Carl Kiekhaefer's trade name for ignitions at Mercury Marine and the name was carried over to the Mercruiser product. as BT Doc stated, its a complete electronic advance amplifier with rev limiter and knock control that is controlled by a hall-effect trigger and fires a separate coil.

think of the TB V like a marine version of the MSD ignitions that people think their cars need.

I see. So, why make things more complicated by having the external main box and external coil when you can have everything in the distributor (HEI)? Is it for knock sensing and rev limiting? Or is the TB better overall?
 

Scott Danforth

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the HEI ignition from GM is simply an electrical "trigger" for the coil. it is a mechanical AND vacuum advance distributor. it was simply one step above a set of points. it is no-where anywhere in the same league as the Mercruiser Thunderbolt ignition.

The TB V has knock control, shift interupt control and it truly an electronic ignition with full electronic advance. it is about 100,000,000 times more sophisticated than GM's HEI distributor.

GM finally put everything that is in the TB V into an ignition system to replace its HEI in the 90's. its called the Delco Voyager system.... and guess what, it has an external box, external coil, etc. to put everything inside the disributor would have a distributor too big in diameter to fit on the motor.
 

poconojoe

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the HEI ignition from GM is simply an electrical "trigger" for the coil. it is a mechanical AND vacuum advance distributor. it was simply one step above a set of points. it is no-where anywhere in the same league as the Mercruiser Thunderbolt ignition.

The TB V has knock control, shift interupt control and it truly an electronic ignition with full electronic advance. it is about 100,000,000 times more sophisticated than GM's HEI distributor.

GM finally put everything that is in the TB V into an ignition system to replace its HEI in the 90's. its called the Delco Voyager system.... and guess what, it has an external box, external coil, etc. to put everything inside the disributor would have a distributor too big in diameter to fit on the motor.
OK, you explained a lot. Thanks for enlightening me!
 
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