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post #1 of (permalink) Old 10-12-2000, 09:09 AM
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Performance spark plugs / gap

Could all the "old timers" tell me what their perferred spark plug brand/type is, and which gap will give the most performance on a stock (SSI ignition) I6 258 engine?
Also, what should they cost me, and if my plug wires haven't been changed since 1980, do I need new ones? :-)

Jedidiah Smith
1980 Jeep CJ-7 I-6, 258 stock for now
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post #2 of (permalink) Old 10-13-2000, 09:40 PM
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Re: Performance spark plugs / gap

You need new plug wires every few years, like no more than about 5 years, and that's only if you have the very best to start with.
There is a lot of new technology going on with plug wires right now, but it will take a few months to years to hit the market....

Just because the vehicle runs, doesn't mean that the plug wires are working correctly.
If you are hearing ignition noise on the radio, especially on the AM band, replace the wires, cap and rotor.
If you find stiff wire insulation, cracks, burned places, cut insulation, boots that won't seal water tight, or connector clips that don't 'snap' into place, replace the wires.

The best way to test is with a scope.
Short of that, when you get new plug wires, and you have them cut and assembled for install, take a resistance reading on each wire, and write it down in your manual.
Every wire will have a different resistance.
When the resistance goes up, time to replace wires...

You can find a bad plug wire or spark plug with a vacuum gauge, believe that or not....

MSD makes an 8.5 MM 'RED' set of wires that are OUTSTANDING.
Best thing on the market right now! About $80 a set though.

Other than that, a plane old set of AutoLite wires for about $20 are about as good as any of the others... Stock replacement or aftermarket.

As for your spark plug gap, that will depend on if you intend on going to the large cap and rotor, and good plug wires, or staying with the small crappy cap and rotor.

If you stay with a small cap, you had better cut your losses and stay with 0.032" to 0.035".

If you change to the large cap and rotor (Basic TeamRush Upgrade), open the gap up to about 0.040"

If you do the cap, rotor, plug wires, and ignition coil upgrade, (Level 2 TeamRush Upgrade), then open the plug gaps up to about 0.045"

If you do an MSD module upgrade, you can stick with about 0.045" but the module will make the difference up in a BIG way!

Here is the 'TeamRush' ignition upgrade article for you '80, 258 CID I-6.


For 258 I-6, '78 to '90

The cap adaptor is the bottom half of a two piece distributor cap arrangement that Ford has been using for over 20 years with great success.
The cap adaptor raises the distributor cap up away from the distributor housing, making it harder for the spark energy created by the ignition coil to go to ground and cause an ignition misfire.
Cap Adaptor.
82 Ford F-150 Pickup, with 300 CID I-6, about $5.
Wells (Auto Zone and others) P/N F-960
GP Sorensen (Advanced Auto and others) P/N FR-109
Delco P/N F-334

Make sure it's the screw down type, and not the quick clip type.
(Adaptors are attached with screws or quick clips, All the distributor caps are quick clip)

Wider cap spreads out the plug wire terminals. This extra spacing helps prevent cross fires of ignition energy. Brass terminals also conduct electricity much better than cheap aluminum terminal caps. These updated caps have spark plug type terminals and use late model high energy plug wires.
The taller rotor keeps the spark energy from jumping to ground through the distributor shaft, or to the distributor housing.
Cap & Rotor,
Premium, brass terminals, For 82 Ford F-150 Pickup, with 300 CID I-6, about $15.
(Auto Zone) Conrad P/N F-2104-G
(Advanced Auto) Standard Blue Streak P/N KCR-202X

Changing to high energy style plug wires is mandatory when you upgrade the distributor cap. Late model plug wires will deliver more of the spark energy to the spark plug, and have better insulation, and terminal ends than the out dated stock type spark plug wires.
Spark Plug Wires,
Premium store brand, For '86 Ford F-150 Pickup, with 300 CID I-6 WITH E.E.C. for the correct coil wire for the E-core (TFI) coil (spark plug boots on both ends of the coil wire for the E-core 'TFI' style coil),
Without E.E.C. for the correct coil wire for the factory stock can coil, $20 to $50.
Look for spiral core wires if you can find them.
Stay away from solid core wires.

The E-core (TFI) style ignition coil is a terrific upgrade to any stock DuraSpark ignition.
It nearly doubles useable spark energy over canister type coils, and has the much more desirable spark plug type terminal.
It's a direct replacement for the canister coil on Jeeps '78 to '90.
For 86 Ford F-150 Pickup, with 300 CID I-6 WITH E.E.C. for the TFI COIL.
(Advanced Auto) GP Sorensen P/N GC-407 S, about $45. Premium Recommended.
(Advanced Auto) GP Sorensen P/N GC-407, about $15. Economy.
(MSD) TFI Premium Coil, P/N 8227, $45.
(NAPA) TFI Premium Coil, P/N IC24, $48.

For 84 Ford F-150 Pickup, with 300 CID I-6 Without E.E.C., CAN COIL
(MSD) Ford Round 'Can' Premium Coil, P/N 8205, $33.


If you change from a canister coil to a E-core (TFI) style coil, you will need to change the coil connector.
Coil Connectors,
(NAPA) TFI Coil Connector, P/N ICC1, $13.
(Standard Ignition) Motorcraft TFI Coil Connector, P/N S-539 $11.

(NAPA) Ford Round Coil 'Horse Shoe' Connector, P/N ICA102, $8.50.
(Standard Ignition) Motorcraft 'Can' Coil Connector, P/N S-583, $5.

You DO NOT have to replace the module on the DuraSpark ignition system, it will power the system adequately in most low RPM, stock configuration situations.

If you decide to enhance your ignition system, the most cost effective upgrade you can make it adding a MSD 6 series module.
MSD increases all useable spark energy levels 100 to 1,000 %, and for the basic 6 series module can be had for around $135.

MSD 6A, most basic module that provides real Capacitive Discharge and Multiple Spark Discharge. Around $135.
MSD 6T, MSD 6AL, up to $175.
MSD Off Road, Up to $250.

All items listed are very easy to install, and everything except the E-core coil and MSD module require NO MODIFICATION at all.
They are all direct replacement parts for tune up parts you have to change anyway.

See Attachement for picture of cap and rotor upgrade parts.

"I Have The Body Of A God... Buddha"
Attached Images
File Type: jpg 9-236685-Cap&RotorComp.jpg (19.4 KB, 1 views)
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post #3 of (permalink) Old 10-13-2000, 10:30 PM
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Re: Performance spark plugs / gap

Man, you can't buy information like this. Go Team Rush!!!!

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post #4 of (permalink) Old 10-14-2000, 10:41 AM
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Re: Performance spark plugs / gap

TR: THANK YOU THANK YOU THANK YOU! I really mean it. I'm going to do the TR upgrade as soon as I get the money.

Jedidiah Smith
1980 Jeep CJ-7 I-6, 258 stock for now
post #5 of (permalink) Old 10-16-2000, 12:40 AM
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Re: Performance spark plugs / gap

No, you can't buy information like this!!
I don't have anything to gain from this, and I've spent a very large part of my life flicking the fly sh*t out of the pepper to find out what works, and what doesn't...

This is too easy to do, and doesn't cost a fortune, and will DIRECTLY benefit your vehicle, unlike the 'Miracle' gadgets like the 'Turbo Rings' that go under the carbs, or all the other crap....

We are trying to put this on a disk, but I need someone in my area to help with building the web pages, an somewhere that will allow us web space with our own name to post it... Like real cheep!! (Free even!)
I have the web space provider, but I still need to build the pages.... I'm not very good at that, and I'm not going to pay someone $80 an hour to do it when there is nothing in it for me....
I don't mind killing time, but blowing $80 an hour for several dozen hours is not something I'm going to do.
(I like you guys, but that's perfectly good beer and ammo money!!)

If any of you live around southern Indiana, and want to donate quality web page building skills, I'll be glad to put you in the credits!!

Later folks....

Help me build my web site, and you may get to go to the machine gun range with me!!
It happens more often than you might think!!

"I Have The Body Of A God... Buddha"
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