A better coil???

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Jan 1, 2004 | 10:39 PM

89blkvet

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From: San Lorenzo Ca

A better coil???

I have done a ton of mod's to my engine, bigger cam, bored block, hypertech chip, new pistons and crank, bearings, etc. I am running the stock ciol, plugs, wires, etc. I am looking for suggestions on the coil, plugs, and the other stuff I just mentioned. Also, does anyone know how many volts a stock coil puts out?? By the way, I have an 89 L-98 eng. Thanks for any and all ideas !!

Jan 1, 2004 | 10:40 PM

scorp508

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From: Boston, MA

What RPM range do you operate at?

Jan 1, 2004 | 10:42 PM

89blkvet

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From: San Lorenzo Ca

Re: (scorp508)

Well I do like to keep my foot in the gas.....high 2's to mid 3's

Jan 1, 2004 | 10:54 PM

jfb

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From: Cincinnati, Oh USA

Re: A better coil??? (89blkvet)

If you aren't defeating the rev limiter and you are running 2k to 4k rpm, your stock coil is fine. Also, the voltage rating doesn't mean squat because that voltage is measured when no spark occurs. Higher voltage doesn't relate to a hotter spark. What is important is the energy (joules) in the spark because when the spark plug gap becomes ionized (spark occurs), the coil voltage is well below 5000 volts and at ionization it is very low. The C4 uses a transistor to switch primary current in the spark coil and the energy is 1/2L(I squared). For more energy I, or current must increase which shortens the life of the spark control module, or L, inductance must be increased, but if you increase inductance, you limit rpm from the increased time to build the magnetic field in the coil. The spark coil is a compromise and GM designed the spark module/coil very well.

Jan 2, 2004 | 12:08 AM

65Z01

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Re: A better coil??? (89blkvet)

You can get some gain from hotter ignition, better wires and cut back plugs gapped wider. For this I like the HyperTech setup as it puts out lots of power for the wider plug gap plus will hold up at higher RPM.

If you upgraded your valve train and raised shift points toward 6k RPM you might want to do the ingitijon upgrade.

Jan 5, 2004 | 07:53 AM

Jim85IROC

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From: Stamford VT

Re: (89blkvet)

Quote:

Well I do like to keep my foot in the gas.....high 2's to mid 3's

Jan 5, 2004 | 09:09 AM

VetNutJim

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Re: (Jim85IROC)

I LIKE the bunny. Pancakes look good toooo.

Jan 5, 2004 | 09:18 AM

VetNutJim

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Re: A better coil??? (jfb)

jfb.... EXCELLENT EXPLANATION!!!!

I think you just talked me outta installing my new Hypertech coil....
Sounds like it "could" adversely affect the life of the ignition module.

But.... since the driver transistor SHOULD be running in saturated mode during the dwell time, do you think the increase in I Max would cause it to dissipate substantially greater heat thereby shortening it's useful life?

You also explained why my spark tester shows only ~6000 volts at the plugs.
I forgot to take into account the ionized resistance of the plug junction.

My understanding of ignition systems just moved up another 'step' thanks to your explanation.

Great post... really got me thinking......