Jon's Hellcat

[Paladin06]

I still have stock plugs in my 2015 at 20k on the clock and all street. Am I hearing I need to change plugs. It’s had an 2.85 upper with Boostane and tuned for 3.5 years. Should I change plugs?

 

[jonx96]

I still have stock plugs in my 2015 at 20k on the clock and all street. Am I hearing I need to change plugs. It’s had an 2.85 upper with Boostane and tuned for 3.5 years. Should I change plugs?

Just replied to your pm. If I was you I’d do them. But also I’m pushing the limits of the car and that’s the reason for the yearly check.

 

[Speedy!]

Well, my opinion.

People agonized over plugs on the previous platform. I ran my NGK Iridiums in the old car for years at 16psi boost, race fuel, 93 pump gas. I don't remember ever changing them after I go the temperature range I wanted and I raced that car for 10 years I think.

If it ain't broke don't fix it. I'd guess these Iridium plugs are good for 40K miles ore more on a hopped up Hellcat. With all that's involved in changing them I'm gonna get the max life I can.

FYI Brisk plugs don't have a very good reputation.

 

[fumanchu182]

so what you're saying is i should buy brisk 12s...

 

[RGPIII]

Replaced mine last weekend. These have about 1000miles on them. All still gapped at .022 lived from 93 to Q16 then the switch to E85. they still looked good, after some very hard miles on them.

 

[jonx96]

Well, my opinion.

People agonized over plugs on the previous platform. I ran my NGK Iridiums in the old car for years at 16psi boost, race fuel, 93 pump gas. I don't remember ever changing them after I go the temperature range I wanted and I raced that car for 10 years I think.

If it ain't broke don't fix it. I'd guess these Iridium plugs are good for 40K miles ore more on a hopped up Hellcat. With all that's involved in changing them I'm gonna get the max life I can.

FYI Brisk plugs don't have a very good reputation.

I remember reading something’s awhile back about brisk and people not being happy. But it was all startup or idle related if I remember right. One in particular I remember reading was from a shop who I’ve returned 3 or 4 of their e85 cars and they don’t they don’t tune injector offset, startup properly, and don’t entich it at start for e85. Also the brisk plug isn’t meant to run as long as the Ngk. I don’t plan on them last 20k miles. Another thing if there is detonation or a lean spot the brisk plug will fail which will through a misfire. The Ngk won’t fail as easy and I’d rather take the plug out then the engine.
Also your problem isn’t the plug itself it is the stock gap. You are making over 20psi now. Gapping down is needed. I went .021. Factory is like .034 I think maybe .032.

so what you're saying is i should buy brisk 12s...

What’s your gap on the if I remember right Ngk

 

[jonx96]

Replaced mine last weekend. These have about 1000miles on them. All still gapped at .022 lived from 93 to Q16 then the switch to E85. they still looked good, after some very hard miles on them. View attachment 97040

Yep look good and so did mine. But I had a stock plug in bad shape when I changed it so I told myself I’m going to do this yearly.

 

[RGPIII]

Yep look good and so did mine. But I had a stock plug in bad shape when I changed it so I told myself I’m going to do this yearly.

Yup I’m the same way. Replace mine yearly regardless if they need to or not.

 

[jonx96]

Yup I’m the same way. Replace mine yearly regardless if they need to or not.

glad I’m not the only one. Do you ever do leak down tests?

also this is the only platform where people are leaving stock plugs in at such high boost. It is way more of a pain than other platforms but during the winter months isn’t bad to take part of a day and do them.
Did you put Ngk back in?

 

[RGPIII]

glad I’m not the only one. Do you ever do leak down tests?

also this is the only platform where people are leaving stock plugs in at such high boost. It is way more of a pain than other platforms but during the winter months isn’t bad to take part of a day and do them.
Did you put Ngk back in?

Haven’t had to do a leak down on it yet. Nothing jumped out at me with the plugs so no need for it I don’t think.
Yup went back with another set of NGK 2309’s. I’ve had good luck with them on both my hellcats. Gapped to .022

 

[vortecd]

Haven’t had to do a leak down on it yet. Nothing jumped out at me with the plugs so no need for it I don’t think.
Yup went back with another set of NGK 2309’s. I’ve had good luck with them on both my hellcats. Gapped to .022

NGK 2309 for me also

 

[Marc W]

 

[DavidKFla]

The problem gets to be the gap when adding boost. But plenty of people have done it with stock plugs at your boost. But personally I’d at least do an ngk plug happed to .026 or .028 at your boost.

I'll have

NGK 2309 for me also

Are 2309s stock? That's what was put in my car.

 

[vortecd]

I'll have


Are 2309s stock? That's what was put in my car.

No ngks are not the stock plug

 

[jonx96]

View attachment 97048

Hey Marc that would make me think twice about a yearly plug change at that price

 

[vortecd]

Hey Marc that would make me think twice about a yearly plug change at that price

Thought it was 8 plugs but see it is 1

 

[Marc W]

Thought it was 8 plugs but see it is 1

X16! 🫣

 

[DavidKFla]

I'm seeing 16 plugs for the $120 range if it's the right ones.

 

[Marc W]

Hey Marc that would make me think twice about a yearly plug change at that price

That’s for sure. 😂

 

[Speedy!]

I ran NGK 6619 gapped to .028 in the old car. I might have gone to 2309s too hard to remember now.

When I need to swap plugs I'll probably use 2309s at .028 but not gonna fool with them until I need to. Car is running well as is and I'd be more worried about causing a problem. I've seen several gave misfire issues after plug swaps and it turn out they damaged a coil during the change out.