Good better best plugs etc

[driver007]

Does the AMC 258 i6 / 4.2l free of mods prefer a certain brand of spark plugs? Is there any neg traits noticed with certain brands when it comes to the AMC 258 i6 / 4.2l ? I have seen in the past oil filter debate but I was curious if there is a debate on stockish air filters?

 

[steve1973]

You are going to get lots of passionate brand loyalty responses, so get ready. For my 73, I have tried champion, autolites (standard and platinum) e-3's and Nippon Iridiums. Without a doubt the Nippons have given me the best mileage, cold weather starting and seat of the pants increased power feel. Standard autolites would be second, and the rest all gave me a slightly less overall impression, similar results.


Sent from my iPhone using Tapatalk

 

[IOPort51]

I do not see enough difference to start a good discussion, much less an argument. I have a dislike for NGK s but for no good reason I can remember.

 

[driver007]

I know there will be brand loyalty. But I have some machines that do run better on certain types of plugs. So I was wondering if that is the same with a AMC 258 i6 / 4.2l ? It seems I have been running into some plugs lately that were bad right from new. Different brands to boot. Ok so what is better running or is this to subjective and just put some plugs in and go

 

[Woolyworm]

I run autolites in my AMC 304 with 0 issues


Wooly

 

[Torxhead]

As long as I have been on forums Autolites seem to be the plug of choice. Adding a dedicated ground to the heads and good plug wires can insure a good electrical connection.

 

[IOPort51]

As long as I have been on forums Autolites seem to be the plug of choice. Adding a dedicated ground to the heads and good plug wires can insure a good electrical connection.

I never thought of there being a problem grounding through a head gasket but I guess it could happen.

 

[elwood blues]

I have seen in the past oil filter debate but I was curious if there is a debate on stockish air filters?

Google search AMC 258 i6 / 4.2l spark plugs, there are more than a few ridiculous arguments on other forums, from every internet know-it-all you can think of about which spark plug is the "correct" spark plug or which one is the "best" spark plug...

This is the perfect example of the saying Your Mileage May Very (YMMV), so many factors go in to how "good" a spark plug is, overall condition of your engine, ethanol percentage of your fuel, where your fuel was refined, your elevation above sea and on and on.

There are some basics, you really don't need a platinum or iridium spark plug in the AMC 258 i6 / 4.2l 's, they were never designed to need that much heat in the combustion chamber for optimal combustion, a copper plug will work sufficiently. As for what brand, that's completely up to you.

I'm currently running E3 spark plugs, I really don't think they're worth the hype, or the price tag

 

[Torxhead]

I never thought of there being a problem grounding through a head gasket but I guess it could happen.

Cast iron is not a great conductor either, especially over a distance.

 

[hagar]

Champion factory AMC/Jeep spark plug.

 

[Lumpy Grits]

Been run'n 985 Autolite's in my AMC 258 i6 / 4.2l for over 25 yrs.
Use some copper anti-size on the plug threads.
LG

 

[Hedgehog]

I run champions, why, naturally because someone said they were the cheapest, but if changed every couple years they were the best.

File the following under, "Just for laughs."

Naturally after reading about how difficult it is to ground a jeep I run a separate ground wire from the battery ground post to each and every plug, none of that cheating by running several plugs on one wire, no sir a separate wire to each and every plug. Of course several ground wires to the engine, Transmission , Transfer Case , body panels, steering wheel, the rubber on the tires and many other parts, some of them will never see an electrical connection, but you never know when you might need your windshield grounded. The wire bundle coming off the negative terminal is the size of my wrist and needs to be held up with a bracket of it's own, naturally that is grounded as well......

 

[Dolf]

I was curious if there is a debate on stockish air filters?

I run K&N’s on everything including my Harleys. I did not check the mileage on my CJ’s, but the biggest improvement was on a Cavalier. It went from 30 city/highway to 33 city/highway. It also seemed like the squirrel didn’t have to push as hard. I know that’s apples and oranges, but it’s an example of the improvement that you can get.

 

[Morris4x4Center]

As others say, if the factory plug was copper (the choice of the engines engineer), than that should be fine. It could depend on the year of the engine though as to what part number to use.

While you can upgrade to a platinum or iridium plug, it's hard to say if that would be better without a whole lot of engineering science. Some modern engines will only run on a specific kind of plug (such as those with SFI, or unusual like a Rotary engine).

Platinum plugs do last longer, but that's usually with fuel injection.

If that's any help. :-)

 

[Lumpy Grits]

I run K&N’s on everything including my Harleys. I did not check the mileage on my CJ’s, but the biggest improvement was on a Cavalier. It went from 30 city/highway to 33 city/highway. It also seemed like the squirrel didn’t have to push as hard. I know that’s apples and oranges, but it’s an example of the improvement that you can get.

K&N lets far more crud into the engine than any paper filter does.
LG

 

[Hedgehog]

Lumpy - I love yeah man, another long held belief, "K&N makes great air filters", shot down in flames. I've been running K&N filters in dusty Arizona conditions for years on about all my vehicles and never knew how much damage I was doing to my engines.

 

[Peanut Butter]

Naturally after reading about how difficult it is to ground a jeep I run a separate ground wire from the battery ground post to each and every plug, none of that cheating by running several plugs on one wire, no sir a separate wire to each and every plug. Of course several ground wires to the engine, Transmission , Transfer Case , body panels, steering wheel, the rubber on the tires and many other parts, some of them will never see an electrical connection, but you never know when you might need your windshield grounded. The wire bundle coming off the negative terminal is the size of my wrist and needs to be held up with a bracket of it's own, naturally that is grounded as well......

But you forgot to ground your soft top! :wasted:Never know! Rod

 

[Lumpy Grits]

Lumpy - I love yeah man, another long held belief, "K&N makes great air filters", shot down in flames. I've been running K&N filters in dusty Arizona conditions for years on about all my vehicles and never knew how much damage I was doing to my engines.

Just one of many tests done to show how poor a job K&N does.
BTW-IF, K&N was so great- Why aren't they OEM on any car/truck made today or ever has been made?

Read this, and you will see what K&N doesn't do--
Filtration Testing for Amsoil, K&N, Napa, Jackson Racing, Baldwin, and Mazda air filters on a Miata

K&N Air Filter Review - Debunking the Myths (and why OEM is better)

I run WIX paper, and will continue to do so.
LG

 

[Dolf]

Just one of many tests done to show how poor a job K&N does.
BTW-IF, K&N was so great- Why aren't they OEM on any car/truck made today or ever has been made?

Read this, and you will see what K&N doesn't do--
Filtration Testing for Amsoil, K&N, Napa, Jackson Racing, Baldwin, and Mazda air filters on a Miata

K&N Air Filter Review - Debunking the Myths (and why OEM is better)

I run WIX paper, and will continue to do so.
LG

“I've been running K&N filters in dusty Arizona conditions for years on about all my vehicles and never knew how much damage I was doing to my engines.”
If you have been using K&N for that many years in a dusty climate, it would be interesting to know how many miles you have driven with the K&N, and what damage, if any, you have had.

“Why aren't they OEM on any car/truck made today or ever has been made?”
K&N would cost the car companies much more money. What do they pay for a filter now? A buck? It's just like politics - follow the money.

Thanks for the great information especially:
K&N Air Filter Review - Debunking the Myths (and why OEM is better)

Although the test parameters are good on the first article:
Filtration Testing for Amsoil, K&N, Napa, Jackson Racing, Baldwin, and Mazda air filters on a Miata

the author is taking the images at an angle to the subject therefore changing the results, so I would not put too much credence in the photographs. I’m going to buy some other filters and see how much my MPG’s drop and balance that with the filtration qualities.

 

[Dan86CJ7]

get factory campions from my parts dept. RFN14LY