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Shiny Metal Titanium
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Discussion Starter #1
Well.. spark plugs are fairly cheap. Especially when you only need 4 for a 4 cylinder.

Are there any advantages to running one over the other other than longevity?
 

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If you really want iridium plugs, I highly suggest Rock Auto. You're much better off if you can make an order for more parts at the same time, but their discount on iridium plugs as compared to parts stores is well worth the $8 shipping charge. Of course, check cost effectiveness vs a local store, but it should be good. Their prices on windshield wipers are outstanding as well, and you can use our 5% discount from the Vendor Deals, Group Buys, and Special Discounts forum.
 

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Shiny Metal Titanium
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Discussion Starter #4
Actually I was wondering if there are any effects of going copper
I started searching about the differences and it seems to be good in some cases and bad in others.
The low cost of copper would not affect my budget at all and I figured I could swap those every other oil change.
Sounds a bit wasteful though.. right?
For some reason it seems to me that sticking a new plug in there rather than slightly worn one might be more helpful
 

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I didn't notice a whopper of a difference, but I think you need to use the AR103 plugs which are racing plugs. A103 is the standard plug. Both of those are one step colder than stock to avoid pinging in warm weather. You might see a slight fuel economy increase if you use the A104 in winter, and 103s in the summer. The colder plug helps reduce pinging, and therefore the -10 spark timing that the PCM does when pinging is detected. If you use premium fuel- there's no need to use the colder plugs in the summer unless you have mods requiring more.
 

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After reading a bunch about this sometimes much-hyped topic, I went to copper Autolite 104s. The main reason I went with 104s vs. 103 (which supposedly offers some slight performance gains) is because I routinely take short trips in the car. And I don't want to run a plug that fouls because it's not hot enough.

The copper 104s were said to smooth out a sometimes less than smooth idle vs. iridiums (even when new). And... they did. I'll have to change them more frequently but there's just a certain something about a smooth idling car. That's my take[cool]
 

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Shiny Metal Titanium
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Discussion Starter #9
Where did you get the 104s? I haven't found a local place with them yet
I now take a lot of short trips.
I drive ~0.3 miles to work and sometimes the car doesn't get to warm up before I get there, same thing with the trip back after work
 

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Where did you get the 104s? I haven't found a local place with them yet
I now take a lot of short trips.
I drive ~0.3 miles to work and sometimes the car doesn't get to warm up before I get there, same thing with the trip back after work
Auto Zone
 

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A while back, (as this is a recurring topic), someone actually did dyno runs that proved the copper plugs gained a LITTLE H.P. over all the others, WHICH others didn't matter....

Downside was the need to replace them frequently to keep the gains, or even keep running "normally"....

As mentioned, they worked GREAT in cars for years, and the fancy newer ones have advantages ONLY in the lack of need to change them often.... (relatively...)

Luck!
 

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I can't seem to find a A104
That's what the parts guy will pull up when you ask for an Autolite plug for your car. It's there even if you can't find it online.

The AR plugs are harder to find, and as Sailor mentioned those are the ones that Turbo Tom proved to give a 3 hp gain on the dyno.

Heat range is slightly misunderstood in this thread. You're not waiting for the plug to heat up. The second job of the spark plug, after sparking, is to remove heat from the combustion chamber. In this respect, think of the spark plug as a high speed connection between the combustion chamber heat, and the coolant passages around the plug hole. That's where heat range comes in, and you can physically see the difference in the insulator around the center electrode. More of an insulator= higher heat range= less heat removed from the combustion chamber. The reverse for cold plugs.

This is why you run colder plugs in higher performance vehicles because the combustion chamber is already being over heated as compared to stock. You want as much heat as possible removed before the next A/F charge comes in, or you could get detonation (before spark). Since lower octane fuels burn faster, the colder plug would do better to prevent the same detonation (pinging, spark knock) with low octane fuels in a stockish vehicle. In our particular case we're trying to avoid spark pull as a result of the knock sensor noticing spark knock. In the winter when air temps are lower, it's less of an issue, and in this case a colder plug is not needed- possibly hindering.

I run colder plugs yearly, but I don't run the AR plugs. In the winter I block off airflow to part of my radiator. I'm not recommending this for your car because there are differences between the thermostats of the 05 as compared to 09. My car came factory with a 180 degree thermostat, and no coolant temp sensor on the thermostat housing. You'd overheat if you did the crazy things I do to keep my engine temps right around 200F even in sub zero temps.

I just threw that swapping out depending on the seasonal temps thing in there since you seemed to want to swap plugs every other oil change. That's too much swapping IMO. Old spark plugs will last 20k miles, and to be frugal you should swap only after inspecting. Believe me, back in the day, people ran those plugs for like 60k miles- sort of like they do now with fuel filters. You could even run those plugs for 40k under ideal conditions, and not have any detrimental effects if you cleaned the plugs regularly- say during your "tune-up"/oil change. A wire brush, a small bladed knife, and a gap tool is all you need.
 

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NGK TR55GP plugs FTW!!
 

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Shiny Metal Titanium
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Discussion Starter #14
That's what the parts guy will pull up when you ask for an Autolite plug for your car. It's there even if you can't find it online.

The AR plugs are harder to find, and as Sailor mentioned those are the ones that Turbo Tom proved to give a 3 hp gain on the dyno.

Heat range is slightly misunderstood in this thread. You're not waiting for the plug to heat up. The second job of the spark plug, after sparking, is to remove heat from the combustion chamber. In this respect, think of the spark plug as a high speed connection between the combustion chamber heat, and the coolant passages around the plug hole. That's where heat range comes in, and you can physically see the difference in the insulator around the center electrode. More of an insulator= higher heat range= less heat removed from the combustion chamber. The reverse for cold plugs.

This is why you run colder plugs in higher performance vehicles because the combustion chamber is already being over heated as compared to stock. You want as much heat as possible removed before the next A/F charge comes in, or you could get detonation (before spark). Since lower octane fuels burn faster, the colder plug would do better to prevent the same detonation (pinging, spark knock) with low octane fuels in a stockish vehicle. In our particular case we're trying to avoid spark pull as a result of the knock sensor noticing spark knock. In the winter when air temps are lower, it's less of an issue, and in this case a colder plug is not needed- possibly hindering.

I run colder plugs yearly, but I don't run the AR plugs. In the winter I block off airflow to part of my radiator. I'm not recommending this for your car because there are differences between the thermostats of the 05 as compared to 09. My car came factory with a 180 degree thermostat, and no coolant temp sensor on the thermostat housing. You'd overheat if you did the crazy things I do to keep my engine temps right around 200F even in sub zero temps.

I just threw that swapping out depending on the seasonal temps thing in there since you seemed to want to swap plugs every other oil change. That's too much swapping IMO. Old spark plugs will last 20k miles, and to be frugal you should swap only after inspecting. Believe me, back in the day, people ran those plugs for like 60k miles- sort of like they do now with fuel filters. You could even run those plugs for 40k under ideal conditions, and not have any detrimental effects if you cleaned the plugs regularly- say during your "tune-up"/oil change. A wire brush, a small bladed knife, and a gap tool is all you need.

Now I'm confused. [8]
So I can run the AR103 in the winter and it's ok if I make such short trips?(if I can find them and they are the ones that provide the slight hp gain) and can go with the A104s if not
 

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I've really had my heart set on trying these new BOSCH Plat/Ir Fusion plugs for a while now. I've heard a lot of people say to just go with the copper and it'll be fine, but I've REALLY been wanting to try these ones, so hopefully it doesn't hurt anything. I may not gain anything other than additional longevity, but I think it'll be cool to try out at least once.

Thus far (since I got my car bran-new in 06) I've just had the stock plugs in and have never had a problem with them. Nearly 6 years on factory plugs is pretty good I guess. If these have lasted me this long with no problems, hopefully the Plat/Ir Fusion ones will last me twice as long and maintain their peak power for the duration that I have them in.
 
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