Cylinder misfire and blown spark plug with LAP3 tune

[KLR STINGER]

The only difference between hks 50003 m45il and m40il is the heat range. They are the same physical fitment

 

[Dustin]

Incorrect. Stock are heat range 7 on ngk scale. The hks 45s are equivalent to a 9, with the 40s being 8. I actually think 9 is a little over kill for minor mods ( ie adding 100hp or so) if you were doing a big turbo build the 45s might be more appropriate, but the 40s are probably fine. The gap is the major concern. I wouldn't doubt gaping down stock plugs would likely cure the misfires

Where did you get the heat range number from?

 

[STINGER]

Id dont think the HKS 40 will fit in our cars.

I am using the HKS M40iL gapped to 24, I believe TORK motorsports are using 40s as well. Like @KLR STINGER said, the stock plugs gapped correctly will likely solve the current misfire issues. We decided to go with 1 step colder HKS 40's to avoid making any plug changes again as we add mods to the car.

 

[TJH]

Where did you get the heat range number from?

You can see the equivalent heat specs in the table at the bottom of this page:-- SUPER FIRE RACING-M Series | PLUG | PRODUCT | HKS

 

[Dustin]

You can see the equivalent heat specs in the table at the bottom of this page:-- SUPER FIRE RACING-M Series | PLUG | PRODUCT | HKS

I’ve seen that page. I also posted the plug numbers on the stock plugs. I haven’t been able to find any info on the numbers anywhere. I assumed the 9R was the heat number since there is no -# on the plug. How are you guys judging the heat range based off of the stock plug?

 

[KLR STINGER]

SILZFR7A ...The 7 in the OEM part number is the heat range

 

[Dustin]

SILZFR7A ...The 7 in the OEM part number is the heat range

What is the 9R for?

 

[KLR STINGER]

The 9 is internal code for gap spec and the R is for resistor type plug

 

[Dark_Knight GT]

Has anyone been running the LAP3 on re-gapped stock plugs?

 

[StingMe]

I did some research on this, and sure enough it's common to decrease gap when adding boost to avoid misfires.

Allow me to quote from NGK " Required voltage to form a spark at the gap is directly proportional to pressure. A smaller gap may be required to avoid misfire or flashover". Higher boost means higher pressure.
-----------------------

Friedrich Paschen who discovered Paschen's law empirically in 1889.

Paschen studied the breakdown voltage of various gases between parallel metal plates as the gas pressure and gap distance were varied:

• With a constant gap length, the voltage necessary to arc across the gap decreased as the pressure was reduced and then increased gradually, exceeding its original value.
• With a constant pressure, the voltage needed to cause an arc reduced as the gap size was reduced but only to a point. As the gap was reduced further, the voltage required to cause an arc began to rise and again exceeded its original value.

The curve he found of voltage versus the pressure-gap length product is called Paschen's curve

Paschen's law - Wikipedia

 

[Here4now]

so... have a look at how much oil your PVC values are putting into the mix. Tubine engine can pull oil out of the PVC value and create issues with buildup on the plugs. it you are always push the power plant it can create issues.

 

[Daniel @ K8 Stinger Store]

so... have a look at how much oil your PVC values are putting into the mix. Tubine engine can pull oil out of the PVC value and create issues with buildup on the plugs. it you are always push the power plant it can create issues.

But that sort of build up shouldn’t happen this early in the game, I think most customers are around 2-5k on the OD!

 

[Matthew C]

Ouch.

Sorry to hear about your misfire!

Just to go over a few things with you, you were running the chip on the 91 setting with 91 octane gas?

We have seen a few others with stock motors/no bolt ons or chip have some issues with their plugs (only a few incidents so far).

Lap3/PROS did inform us that the stock plugs should be sufficient to run the chip (unlike the Optima which did not come equipped with plugs sufficient for the tune). I will be contacting Lap3 in Korea and HKS this week to look further into a possible alternative to stock plugs (if needed).

We want the community to know we take all products we carry seriously and always looking out for the best interest of the customer. As soon as I hear back from both Lap3 and HKS I'll be sure to let the community know if we will be requiring a different set of plugs/solution if there is an alternative!

Thanks


I'm pretty sure these will not fit the 3.3TT, just for the 2.0T

chip still blew my non stock plugs

 

[xot1]

chip still blew my non stock plugs

where they HKS M45il plugs?