Re: H.E.I. for 258.
First off, you already have a good ignition.
You need to do a couple of things to make it more reliable...
One is the 'TeamRush' cap, rotor, plug wire and coil upgrade.
The other is the 'Nutter' bypass. If you do the 'Nutter' bypass, you will need to swap your distributor in for one from a '79 CJ-7 with 258 CID (4.3L) engine. (around $50 with exchange)
Just swap yours for a rebuilt, the parts dummies at AutoJerks won't know the difference....
The ignition controlled distributors don't have near enough centrifugal advance, and the vacuum advance is pretty limited also.
The 'TeamRush' upgrade,
The problem is the crap cap, rotor and plug wires that AMC used... Not rated for a high energy ignition, and like to cross fire and cause problems...
If you upgrade to the '82 cap adaptor, distributor cap & rotor, and use the high energy ignition plug wires from a '92 4.2 liter Jeep, you will be truly amazed at the easier starts, better highway manners, more power and an increase in fuel milage.
(USE A BRASS TERMINAL CAP, it's worth the extra money)
All of these parts snap right on your existing distributor, nothing but a phillips screwdriver needed.
You will need,
The distributor Cap Adaptor, the Distributor Cap, & Rotor from a '82 Ford F-150 Pick up with 300 CID I-6.
Don't waste your time with the cheap aluminum terminal caps, even if you have to order it and wait, the brass terminal caps are the thing to have.
You will need a set of plug wires from a '92 Jeep with a 4.0 Liter engine.
Everyone reports these work great and they are rated for a high energy ignition.
I recommend MSD <a target="_blank" href=http://www.msdignition.com>http://www.msdignition.com</a> ignition components when ever you can use them.
Order a free catalog from the home page at MSD and look at all the cool stuff they have. (we like free sh*t!)
The next step of the upgrade is the ignition coil. (Part numbers below)
This will require crimping two spade connectors on the new coil connector, and matching color coding on the wiring harness for the old connector.
1/4" male spade connectors, and push them right in where the old coil hooked up.
(now if you have a coil failure, either type Ford coil can be use, so no matter what the parts store comes up with, you can use it!)
You will have to fabricate a coil bracket for the E-core coil (most people just use angle iron) or you can get a coil bracket from any salvage yard.
NAPA p/n ICC-1 for the coil connector, around $13.
'92 Ford Escort for the ignition coil. Ford Factory E-core coil from the TFI ignition. Around $15 for economy, $45 for factory or premium grade.
This will bring your ignition into the later second half of the 20th century.
If you have around $140 lying around, do the cap, rotor and plug wire upgrade, then order an MSD 6 series module (MSD 6A or MSD Off-Road to be exact)
This will bring your ignition into the last 20 years of the 20th century...
Have you looked for bronze in your oil pan!
I can't believe no one told you not to use a bronze gear on a cast iron camshaft!
I'd suggest pulling the distributor and looking at the gear to see how much is left before I put may more miles on it...
**The only problem with converting it to Ford stuff is reliability. Ford Duraspark modules and pick-up coils, even the TFI modules are not known for reliability. Be sure to carry spare modules if you go that route.
If TFI you'll also need the special socket.**
This guy needs to lay off the sauce...
This is one of those guys that will lie to you for fun...
First off, **converting it to Ford stuff**
You are not, "... Converting to Ford stuff..." like the above clown would like you to believe...
Your Jeep already has Ford's Motorcraft distributor and DuraSpark module & ignition coil in it.
It's traveled tens of thousands of miles with a cap, rotor, and plug wires it was never intended or designed to use.
Fix what's broke, not what's working every day with out complaint....
Second, **Ford Duraspark modules and pick-up coils**
Late model Ford ignition modules are MORE RELIABLE than late model GM modules, and can be replaced at any discount auto parts store (some of the super Wal-Mart's are carrying them now...)
Ford has upgraded the power switching for the modules several times down through the years, and they will handle the most stout ignitions now. (GM has changed nothing about their original 4 pin ignition modules, still just as crappy as the day they were issued)
Some of the WAY off road guys take an extra module because early modules were pretty crappy. Ford corrected them in about '77, and they are find now.
They also carry tons of 'What If?... parts and tools...
(can't say that about GM HEI modules, GM hasn't changed their terrible switching transistors yet!)
If you add a splice to the black wire coming out of the module, and connect that straight to the battery negative post. The ENTIRE primary ignition system grounds through that black wire through the distributor housing.
You will be doing your module (and wallet!) more good than switching to a system you vehicle was never designed for or intended to use....
Third, **TFI modules are not known for reliability.** (This guy really doesn't have a clue...)
As for TFI modules, you won't be using a TFI module, just the E-core coil that every manufacturer is using now, and Ford successfully used with the DuraSpark ignition module and conventional magnetic pickup for years...
I say again, YOU WILL NOT BE USING THE TFI MODULE
The E-core coil...
They are more DEPENDABLE, reliable, higher output of usable spark energy, lower in the stuff you don't want (like EM and RFI noise), and have been used by Ford since '84 and by GM since '74.
(that's right, the GM HEI has an E-Core coil... It's just in the cap.)
Fourth, **If TFI you'll also need the special socket.**
No special socket needed, because like I've already stated, you won't be using the Thick Film Integrated module, you will be using the Jeep factory stock DuraSpark ignition module.
(Besides, it's not a socket, it's a stubby screwdriver with tamper resistant torqx bit...)
Do the search, or start a new post asking for opinions of the 'TeamRush' upgrade for the 4.2L/ 258 CID engine.
I'm sure you will find what you need from the posters here...
Several hundred people have already done the 'TeamRush' upgrade for the factory Motorcraft/ DuraSpark ignition used on all I-6 and V-8 Jeeps from '78 to '90, and I have yet to hear anyone complain about the results or switch to a GM HEI after doing the 'TeamRush' upgrade.