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Did a quick search and suprisingly, I could not find any posts regarding spark plugs... Im sure there are some, but I didnt find any...

Anyways, I want to start doing a couple basic upgrades on the car and one of those would be to upgrade the spark plugs. I have heard Denso is a great company. Any other suggestions? I will probably be upgrading the wires as well...

Let me know what you all think!

Thanks
 

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my tuner highly recomended Denso Iridium plugs when i was having the car put on the dyno.

i think i still have the box somewhere, i'll look for the part number after work.
 

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+ 1 to Denso Iridium plugs used in my spec v and worked quite well :D
 

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I'm not really aware of this on a first hand basis because I've never really worked on a turbo car, but when you increase horsepower/boost you need to go to "colder" spark plugs as well as gapping them differently.

I'm not exactly sure what "colder" means, although I have done different types of spark plug gapping. Would someone with more knowledge in this area inform the rest of us?
 

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Discussion Starter #6
my tuner highly recomended Denso Iridium plugs when i was having the car put on the dyno.

i think i still have the box somewhere, i'll look for the part number after work.
The Denso's that I was looking at, were the Iridium Power. Model # IKH20. Checked out the website and this is what I found:

Iridium Power®
This high-performance spark plug has the world’s smallest iridium center electrode that is a mere 0.4mm in diameter. The tip of the grown electrode is taper cut which reduces quenching and improves firing performance. This combination of DENSO technology provides improved horsepower,
 

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ok i am holding a box in my hand right now.

i am using Denso Iridium Power 0.4mm Iridium, U-Groove tapered cut. #IKH24 and under that it has 5346.

the stock plug says...
NGK IR SILFR6A
 

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Did a quick search and suprisingly, I could not find any posts regarding spark plugs... Im sure there are some, but I didnt find any...

Anyways, I want to start doing a couple basic upgrades on the car and one of those would be to upgrade the spark plugs. I have heard Denso is a great company. Any other suggestions? I will probably be upgrading the wires as well...

Let me know what you all think!

Thanks
What mods are you doing? I won't change the spark plugs unless you mods require you too.
 

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usually if you go to a bigger turbo you need 1step colder plugs, are the pulstar pulse plugs the like really expensive plugs?? and im pretty sure we dont have plug wires
 

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I'm not really aware of this on a first hand basis because I've never really worked on a turbo car, but when you increase horsepower/boost you need to go to "colder" spark plugs as well as gapping them differently.

I'm not exactly sure what "colder" means, although I have done different types of spark plug gapping. Would someone with more knowledge in this area inform the rest of us?
Colder just means there is more ceramic insulation further down the electrodes, which exposes less of plug to the combustion heat and thus runs "cooler". However, plugs have an ideal range. More boost means more oxygen = more HEAT, and so if you exceed the heat range of a particular plug you need to go to a "colder" plug. A colder plug is less ideal for everything except WOT/full boost where the heat range is necessitated by combustion heat.
 

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reviving this dead thread -

What about stage 2 - spark plugs? Stock plugs fine? and also I am running at 35000 miles, should I change my plugs or leave them in till 60000?
 

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^^ old thread i know
so im almost at 30k and will need to swap out spark plugs.. i am looking at ngk 1step colder plugs, im on fred beans and there is a description that says "One Step Colder plugs are only recommended for moderate-heavily modified turbo motors only" Now i am on a stock vf-52, but i am at stage one with 18psi with an ipr top mount and K&N intake. im a few months from stage 2. would it be perfectly ok to swap out my stock plugs for these and have no problems down the road?
 

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^^ old thread i know
so im almost at 30k and will need to swap out spark plugs.. i am looking at ngk 1step colder plugs, im on fred beans and there is a description that says "One Step Colder plugs are only recommended for moderate-heavily modified turbo motors only" Now i am on a stock vf-52, but i am at stage one with 18psi with an ipr top mount and K&N intake. im a few months from stage 2. would it be perfectly ok to swap out my stock plugs for these and have no problems down the road?
I would ask your tuner if you need a one step colder plugs.
 

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^^ old thread i know
so im almost at 30k and will need to swap out spark plugs.. i am looking at ngk 1step colder plugs, im on fred beans and there is a description that says "One Step Colder plugs are only recommended for moderate-heavily modified turbo motors only" Now i am on a stock vf-52, but i am at stage one with 18psi with an ipr top mount and K&N intake. im a few months from stage 2. would it be perfectly ok to swap out my stock plugs for these and have no problems down the road?
I wouldn't mess with colder plugs unless you're pushing over 20 lbs of boost. That's really the only time you may see a benefit - for heavily modified cars it helps mitigate knock at higher boost levels only. At Stage 2 you'll probably do more harm than good during normal driving as you may not get as complete a burn in your cylinders due to less electrode showing.
 

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here ya go some reading materials . http://forums.nasioc.com/forums/showthread.php?t=518633

after a 50plus hp increase you could go one colder .

boost wasnt really the term used it was buy horse power but with more hp comes more boost .

the reason to go colder is the plugs can cool down faster after each fire and have less chance for misfire.
 

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Re: Colder Spark Plug? Safe at Stage 2?

Ok, I know this thread is old, but seemed like the right place to ask instead of having to start a new one.

I am going to TP Stage 3.52 soon and have everything I need. I'm just not sure what I should do regarding the colder plugs. I was thinking of getting them installed before I install the rest of my parts myself, but I'm not sure if this could cause wear on the motor or plugs? Would it be safe running them with my just my Stage 2 for a week or so? Or, would I be better off leaving the stock ones in there for the 3.52 map and doing some datalogs the Eric can tell me if I'm going to need them.

What could happen from running the stock plugs w/ 3.52 while driving hard? Could I have motor issues or will the plugs just foul quicker? Last question, I promise, how often will I have to change these step colder iridiums?

FYI, I go WOT pretty often and consider myself to do quite a bit of "spirited" driving. Also, AutoX every couple of weeks during summer and Drag Strip once or twice a year.

Any help appreciated, thanks
 

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essentially you can misfire or prematurely detonate... i'd go with 1-step colder its not much more expensive than regular plugs.. and not worth risking without it at stage 2+. i dont think it would even hurt at stage 2.
 

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Cool, I have them already so I'll get them installed before moving up to TP 3.52 then. Any idea how long they last until I have to change them? I doubt it's the same intervals as the stock ones, but I don't much about these things.
 
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