I tried all sorts of different plugs in mine, before I performed the TFI/Team Rush upgrade, and nothing seemed particularly happy.

Once I did the upgrade and ran .055" gaps, I found that basic Champions did the best. Not the truck plugs, or anything fancy (like Iridium cores, or none of that snake oil)... just good ol' basic Champions.

 

Hello there I have been using E3 plugs for 4 years great performance. I also used them on my 2005 GTO with a LS2. had a shacking that everyone said was the nature of the beast. This was on idling only. The E3's took that shaking off the engine at idle. I'm a believer used them on all 4 of my vehicles. Fred.

 

I called DUI. They recommend Iridium or Double Platinum with the gap expanded to .050” to .055".

Guys on this forum recommend copper plugs but I don't know if they use DUI stuff.

Either way Autolite rose to the top when I did my search. Autolite Iridium XP985. Autolite 985

 

I called DUI. They recommend Iridium or Double Platinum with the gap expanded to .050” to .055".

Guys on this forum recommend copper plugs but I don't know if they use DUI stuff.

Either way Autolite rose to the top when I did my search. Autolite Iridium XP985. Autolite 985

I use Autolite in my YJ and never ever had any problems !

 

When I ran Bosch Platinums, I had more than 1 have core separation issues, which would cause the platinum core to slip forward and ground against the anode. Usually, I could pull the offending plug (seemed to always be in the #4 hole) force a gapper into it to shove the core back in, and it would run for awhile (several weeks/months) then do it again. After a year, I got tired of that real quick.

Don't be fooled by the whole DUI mystique. It's just an expensive HEI system with a cool logo and 45KV Super Coil.

I wouldn't waste time or money on those exotic metal spark plugs - the technology is the same (except more expensive), and there's a reason copper plugs are still a thing (a 'majority thing,' actually).

 

If your existing plugs are good, clean them up, check gap, finish getting the life out of them.

 

I think I have Champions in there now. I guess when I do the compession test and pull the plugs , I’ll decide whether to use the same brand or not. When I first started running the DUI I ran AC’s. and there was a reason for changing…can’t remember, it’s been a while

 

Either copper Champions or copper Autolites. You don’t need iridium or platinum as those are specifically for newer technology. HEI has been around since the late 70s and all the plugs back then were copper. Open the gap to recommended and let er eat. I’ve always used Autolite coppers in AMC motors and had great luck even when I went to an MSD ignition set up.

 

I've always had problems with Champion spark plugs (mostly in 2 strokes). I like Autolite, AC or NGK.

 

="Mister4x4, post: 41926044, member: 1908567

Don't be fooled by the whole DUI mystique. It's just an expensive HEI system with a cool logo and 45KV Super Coil.

I went to DUI HEI after my DuraSpark modules crapped out and left me stranded a couple times. At the time, it was a quick fix for an annoying problem. I've had no problems with the DUI setup.

 

There was likely another underlying problem that caused the DS modules to STB, since they rarely fail. Regardless, swapping to an HEI-style ignition is certainly an option and preference, and if you're getting what you need from it, all the better.

My point with the DUI is that it's nothing more than a basic HEI set-up with the DUI logo driving up the price, since they were one of the early pioneers with HEI replacement packages, right there along with Jacobs Electronics and MSD. I remember reading about Jacobs back in the '90s thinking I might be interested, and actually thought about making the 100 mile trip to Midland/Odessa to pick one up straight from them, found out they didn't do 'out the door' sales at the time (only resellers), and learned about them basically charging for the package (and some tech support). DUI and MSD survived, but Jacobs was bought by Presolite and faded out.

It's essentially the same as if I were to package up all the necessary parts for a Team Rush upgrade and sell it as a Mister4x4 ignition system for significantly more than just the sum of the parts.

But again, if that's what's working for you, there's nothing wrong with it.

 

Autolite 985's of course. Been using them on my 258 for 40 years now. It's what the ignition system is designed for and not those Iridium type plugs.

 

Platinum and iridium plugs were designed for extended life (60+K miles). They were lifesavers on such vehicles as the early Toyota vans. They morphed into the go to plugs on more modern cars and trucks to extend costly tune up maintenance on many vehicles that have "hidden" spark plugs that require large amounts of work to access.

For older applications, where the tune up regime runs in the 5K mile range,standard copper core plugs are just fine. Older engines run "dirtier" and require more diligence with keeping the plugs clean, so being forced to inspect them more often is a plus.
.

It was standard practice to clean and re gap spark plugs all the way up into the early 70's (when plugs became cheap), extending their life for 10 to 15K miles or till the electrodes wore down.

 

Platinum and iridium plugs were designed for extended life (60+K miles). They were lifesavers on such vehicles as the early Toyota vans. They morphed into the go to plugs on more modern cars and trucks to extend costly tune up maintenance on many vehicles that have "hidden" spark plugs that require large amounts of work to access.

First plug change on my 2001 S10 with 4.3 engine, I cheaped out and bought some cheapie Autolite plugs from Walmart and they failed far short of their factory recommened 100K interval. Next time around I bought NGK (I think) platinums and they're still going past what the Autolites lasted. Changing plugs on that truck is a pain so you try to avoid having to do it as much as you can. And thats one thing you can say about a 258 in a CJ is that it's such a breeze to change plugs. You lift the hood and the darned things are staring right at you nothing obstructing access.

 

Speaking of modern vehicles and spark plugs, my new Tundra's maintenance schedule calls for the plugs to be replaced at 40K miles. It's ridiculous how much crap you have to remove or disconnect just to get to the damn plugs. The dealerships charge north of $500 to replace them. Ugh...

 

Not exactly the same - but I'm running the Holley Sniper EFI / Hyperspark Ignition combo and the Autolite 985 plugs are running great. I gapped them to .045

 

I found a photo of the Autolite 985's I pulled about a 100 engine hours ago. I have an hour meter installed on my engine and go by that instead of mileage.

I'll change them out after 500 hours but engine runs great at the moment. They are gapped to .045" with MSD ignition system, E-core coil and TeamRush upgrade.

 

Well, I don't know what E3 plugs are, and imagine you probably just replaced a set of a bad or worn plugs when you got rid of your shaking. 2005 GTO - VERY cool! I love those cars.

It's like I say when it comes to choosing a mechanic: Everybody has different experiences with them. If you find one you like, stick with 'em.

 

When i replaced the Plugs on the GTO they were top of the line for that engine . And they were only 2 months old when i took them out. I was frustrated with the new plugs not solving the idle shaking. Also Stacy David of Gears online car shows. Has always highly recommended them. There are lot of information on the E3 plugs online showing test result. Also know this. E3's fire all round the Plug. Not firing in one place all the time as does single pole plugs. Witch wears down the single spot on the plug. Increasing the gap as it wears. Fred

 

i picked up a set of E3s for cheap on Rockauto and they look like they are chrome plated to me....i didnt want to take a chance on the plating coming off in my engine. I like Bosch platinums but have run pretty much everything at one point or another and not seen any difference if they are gapped correctly and all the other components are good. Even tried indexing the plugs a couple times to see if it made any difference and from a seat of the pants perspective it was a waste of time.

 

Well, I don't know what E3 plugs are, and imagine you probably just replaced a set of a bad or worn plugs when you got rid of your shaking. 2005 GTO - VERY cool! I love those cars.

This.
E3's are a gimmick, Much like 2 and 4 electrode plugs. The concept is to reduce fouling, an issue not really seen in any modern engines. The other thought is longevity due to the spark using the path of least resistance, which can be shared between multiple electrodes. Now there are iridium plugs with 60+K mileage ratings, this argument doesn't hold water any more either.

Some 2 electrode plugs claim to unshroud the spark, but this has no real bearing on the average engine either. If there were any noticeable improvement in any engine metric, the plugs would be standard on all cars struggling to pass emissions.

Even tried indexing the plugs a couple times to see if it made any difference and from a seat of the pants perspective it was a waste of time.

Indexing plugs was a fad with HP dragsters up through the 70's. The thought was to point the electrode away from the intake valve in order to give the spark path a direct line to the incoming charge. Again, perhaps there is a marginal difference in a sub 7 second dragster, but really there is no difference in an average motor.

 

You only use NGK green plugs in a Jeep 3.7L motor. Nothing else. Those are factory used plug that come from the day they roll off the line.

 

All you ppl using everything but the literally plug they were designed around Dammit. Do u understand your motor at all? NGK green is the best plug for a Jeep 3.7L motor. Stop literally wasting money. They were designed around one plug and one plug only. Know your motors or get ur tuneups at Jeep dealership. All of you

 

Eh? The Jeep 232 and 258 engines probably go back before NGK's were even in existence.

 

Well Fiats would properly use an NGK.

 

NGK green plugs are what they are rolled off the floor to dealer with when they were brand new that’s the only plug you use. Champion are garbage.

First of all, as many have pointed out, 'real Jeeps' never came with 3.7L V6s. Strike One.

All you ppl using everything but the literally plug they were designed around Dammit. Do u understand your motor at all? NGK green is the best plug for a Jeep 3.7L motor. Stop literally wasting money. They were designed around one plug and one plug only. Know your motors or get ur tuneups at Jeep dealership. All of you

Yo, Bag o' Doosh - wrong forum. Strike Two.

You might want to check your attitude at the door. This is the Jeep CJ Forum. Our real Jeeps never came with a 3.7L engine, and they certainly didn't come with NGK plugs in them.

Regardless of what model you have, what your background is, or which forum you're in or from, don't be a d!ck. Strike Three.

So, toddle on off back to wherever you came from and go sort out your mall-crawler dashboard ducks, kiddo. The adults are trying to have a conversation here.