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1 step colder spark plugs

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Location
Maryland
#1
Looking to change the spark plugs to 1 step colder spark plugs. Have a '19 FiST and I know Dizzy sells them pre-gapped on their website. Went on Advance Auto to see if there was a price difference and they state they don't fit the '19 FiST? But of course also see elsewhere that they do fit. NGK/Denso spark plugs shouldn't be longer than Motorcraft plugs right? Just confused lol
 


OP
Z
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Location
Maryland
Thread Starter #3
That's what my initial thoughts were!! Just the conflicting information was making me doubt myself lol
 


OP
Z
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Thread Starter #7
Do you have an e30 tune? I'm very excited to see what it's all about!
 


Sam4

Senior Member
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West Chester, PA, USA
#8
Chain store/parts stores will never deviate from the computer parts catalogs. They're right - colder plugs are not the correct plugs for a 2014-19 ST. It's like buying tires at Costco - oem spec only.
 


TyphoonFiST

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Rich-fizzield
#9
Do you have an e30 tune? I'm very excited to see what it's all about!
Had* It will make you want more power. Its where it all started for me. Now I'm E50... BT...4 port Aux...Yuge intercooler...blah blah blah. I said I would never Mod it also....in the beginning!


Sent from my SM-N975U1 using Tapatalk
 


Messages
354
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364
Location
Maine
#10
When I went from regular denso plugs with 20-30k on them, to the NGK 1-steps it was a night and day difference in drivability. I had the Dizzy Stage 2 tune for about a year on the stock plugs and just switched them over a few days ago, It really woke it up, smoothed out the idle and just made it pur. Best $50 I ever spent. lol
 


OP
Z
Messages
16
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4
Location
Maryland
Thread Starter #11
Had* It will make you want more power. Its where it all started for me. Now I'm E50... BT...4 port Aux...Yuge intercooler...blah blah blah. I said I would never Mod it also....in the beginning!


Sent from my SM-N975U1 using Tapatalk
Well, I'm sure i'll get there eventually haha
 


gtx3076

1000 Post Club
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#14
This is why I will not go one step colder, unless I get a tune for which the tuner explicitly demands the colder plugs use, for safety's sake.
I run ethanol most of the time. I occasionally see very minor negative corrections, but no more than when I ran step colders.

I'll see how the tune does with Texas summer around the corner. I won't switch back to step colders unless the car is telling me it needs it.
 


SteveS

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Osage Beach, MO, USA
#16
I’ve got a custom tune from Randy @ Mountune and he said plugs won’t make a difference unless I change to a non stock turbo.
^^^This. You only need colder plugs if the plugs you are using are overheating. They don't fix driveability. The only thing you would possibly notice as a symptom you need colder plugs is preignition. The way to tell if you need to change heat range on plugs is to look at the tip of the plug.

If you run too cold plugs, you will get fouling. And driveability problems.

The gains that come from a tune by itself, or intake changes, will not warrant a colder plug. Internet stories notwithstanding. There's a strong placebo effect with changing parts. Purveyors of speed equipment depend on it.
 


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160
Location
Charlotte, NC
#17
I went with one step colder NGK’s after flashing Dizzy’s stage 1 tune as is recommended by Dizzy. I’m sure the stock plugs would have been totally fine but I’ve got no drivability issues on these and it cold starts like normal. First few cranks on these after installing were a little longer but after a few days of driving it’s now cold starting just as quick as the OEM plugs. Not sure how that works but that’s been my observation for what it’s worth.

I do relatively short trips during the (normal) work week of 10-15 mins driving time so we’ll see how they do as far as fouling. But worst case, I’d rather use the recommended plugs by my tuner and have some (potential) extra safety from preignition and just change them sooner if they foul. YMMV however
 


Messages
41
Likes
10
Location
Florida
#19
^^^This. You only need colder plugs if the plugs you are using are overheating. They don't fix driveability. The only thing you would possibly notice as a symptom you need colder plugs is preignition. The way to tell if you need to change heat range on plugs is to look at the tip of the plug.

If you run too cold plugs, you will get fouling. And driveability problems.

The gains that come from a tune by itself, or intake changes, will not warrant a colder plug. Internet stories notwithstanding. There's a strong placebo effect with changing parts. Purveyors of speed equipment depend on it.
Do you happen to know what the gap is for factory plugs?
 


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