Spark plug gap?

[SHOZ]

Yes either they got special plugs or they regapped them before install. As far as i know all the turbos came like that.

http://www.gencoupe.com/2-0t-discussion-2008-2012/58215-what-your-factory-spark-plug-gap-10.html

 

[Vikas]

Call me stupid but I am not going to trust few Hyundai knuckleheads on a forum over the factory documentation.

Reading that topic immediately tells me that neither of the guys writing there has seen his 30th birthday yet aka it is all baloney. The days when spark plug gap made a difference in the running of a engine went away with high voltage electronic ignition.

If you think you can take .40 plug from the factory and gap it to .30 to get more power from the engine, who am I to stop you?

 

[SHOZ]

Originally Posted By: Vikas
Call me stupid but I am not going to trust few Hyundai knuckleheads on a forum over the factory documentation.

Reading that topic immediately tells me that neither of the guys writing there has seen his 30th birthday yet aka it is all baloney. The days when spark plug gap made a difference in the running of a engine went away with high voltage electronic ignition.

If you think you can take .40 plug from the factory and gap it to .30 to get more power from the engine, who am I to stop you?
OK, howdy stupid. Many when upping the turbos output knock the gap down to the .028.

 

[rslifkin]

Originally Posted By: Vikas
Call me stupid but I am not going to trust few Hyundai knuckleheads on a forum over the factory documentation.

Reading that topic immediately tells me that neither of the guys writing there has seen his 30th birthday yet aka it is all baloney. The days when spark plug gap made a difference in the running of a engine went away with high voltage electronic ignition.

If you think you can take .40 plug from the factory and gap it to .30 to get more power from the engine, who am I to stop you?


Just shrinking the gap will, if anything, hurt power. A larger gap is better. But on a turbo engine when you start turning up the boost, you'll hit a point where you either need to gap the plugs smaller or upgrade the ignition system. If you do neither, you'll start to get spark blowout and misfires at high rpm under heavy throttle.

 

[SHOZ]

You guys can say what you want. I can indeed confirm you will get high rpm misses with the factory gap. I can also confirm the car comes from the factory with a ~.028 gap.

Not that I am offering these facts on an internet forum or anything. The Gencoupe forum is probably the best for that car on the internet. A lot of big builds there as well as the newbies.

 

[PandaBear]

If the OEM (Hyundai / Kia) in this case said 0.32, I'd use that gap.

Other manufacturer may not make 0.32 on their product line pre gapped and they tested 0.40 thinking that it is good enough (let's say you will get 1/1000 chance of misfire vs 1/100000, making your emission a tiny bit less, not a difference in real life but could push OEM's limit in emission score), and it lasting 120k miles instead of 180k miles.

Personally I'd see no reason to alter OEM spec unless I'm modding my car. What's there to gain if you are not running it to the limit on the track? The potential loss is a worn out coil and plug life.

 

[SOHCman]

So they mke it .028 so the spark can survive the forced induction basically?

 

[DoubleWasp]

Originally Posted By: SOHCman
Gap seems to be selected based on how capable a given coil/ignition system of delivering a reliable spark over a given gap.

That said, muscle car V8 guys have been upping the gap (say .044 to .055 on copper plugs) for eons when upgrading to a more powerful coil and better wires, etc.

They wouldn't do it if it weren't reliable and delivered some performance aspect, but that said it's likely a different game for newer vehicles using individual coils.


Nope. Same game. They make coils with increased output that allow you to run a fat gap with no blowout.

 

[kr_bitog]

Not that simple, many coil on plug is smaller than old competition coil, which means the power they produce may not as big as the single big coil even though it will make system more reliable due to redundancy and more recovery time before sparking. However that does not means it will stand too big of plug gap.
The plug gap is also depends on construction and material where big platinum electrode will be the worst and twin small tip iridium will be the best to produce spark.
My experience is if I put too little gap on small electrode plug it may reduce torque, too big gap on standard platinum plug with 1.1 mm center electrode may cause misfire on high rpm.

 

[SHOZ]

On the Hyundai they use COPs and twin tip Denso iridium plugs. When the boost the pressure they usually go a step colder and narrow the gap. Some are at 30 psi. I run around 21 psi peak on the stock turbo. Stock with no tune is around 16 psi that tapers to around 12 psi at redline, 6500 rpm stock.