Mixed answers regarding the Kia Stinger 3.3T - Ultimate Performance HFC Downpipe + Mid Pipe Combo Kit

[StingerMG]

Hello,

I have a 2022 Stinger GT2 and I'm interested in changing the exhaust. The Kia Stinger 3.3T - Ultimate Performance HFC Downpipe + Mid Pipe Combo Kit on the K8 Stinger Store caught my eye but I heard some mixed things about the kit and I have some questions? I'm still learning so sorry if these are noob questions

1. I read that installing the kit will not throw up a CEL, but will the kit create any overboost issues?
2. Can the Kia Stinger 3.3T - Ultimate Performance HFC Downpipe + Mid Pipe Combo Kit be ran reliably (this car is my daily driver) without a tune?

 

[PMR818]

I recently was driving with my JB4 unplugged so the only “tunes” were the Borla catback, Ultimate Performance down and mid, and after-market intake and spark plugs. The car felt plenty fast and fun but I did get over-boost issues often which put a damper on the fun a lot (just boost loss causing the car to accelerate like a Prius until you shut off the engine and restart).

The JB4 helped a lot with lessening over-boost (and adding more power of course) but the real helper on top of it all was buying and installing those JB4 EWG add on connectors — which in essence is a super easy install…and yet I feel like there should be more venting on this board about connecting those suckers assuming you’re someone like me who spent hours sticking their hands through tight engine spaces bc they didn’t remove engine parts for a clearer pathway. But I digress…

My Stinger is also my daily driver and while the gas mileage isn’t ideal (of course partially bc how I drive!) it always is so worth it to me bc it’s such a fun cruiser and bruiser that puts a smile on my face. And I like how loud it is.

 

[StingerMG]

Ah, sounds like the JB4 + the EWG cables are basically a prerequisite before you add the Ultimate Performance down and mid combo.

 

[oddball]

The key is the catalytic converters and the output from the turbo. Change those and you have to tune the car to account for it.

 

[StingerMG]

Makes sense. Sounds like I'll stick with getting a simple Cat-Back for now. I'm still on the fence if I want to get a JB4 down the line.

 

[Daniel @ K8 Stinger Store]

Hello,

I have a 2022 Stinger GT2 and I'm interested in changing the exhaust. The Kia Stinger 3.3T - Ultimate Performance HFC Downpipe + Mid Pipe Combo Kit on the K8 Stinger Store caught my eye but I heard some mixed things about the kit and I have some questions? I'm still learning so sorry if these are noob questions

1. I read that installing the kit will not throw up a CEL, but will the kit create any overboost issues?
2. Can the Kia Stinger 3.3T - Ultimate Performance HFC Downpipe + Mid Pipe Combo Kit be ran reliably (this car is my daily driver) without a tune?

Hey StingerMG,

The Ultimate Performance HFC Downpipe Combo Kit requires a tune in order to work correctly.

Also, this is currently the only available combo kit that does not throw a CEL.

I hope this helps clear things up. ​

 

[Brianlynn0803]

I recently was driving with my JB4 unplugged so the only “tunes” were the Borla catback, Ultimate Performance down and mid, and after-market intake and spark plugs. The car felt plenty fast and fun but I did get over-boost issues often which put a damper on the fun a lot (just boost loss causing the car to accelerate like a Prius until you shut off the engine and restart).

The JB4 helped a lot with lessening over-boost (and adding more power of course) but the real helper on top of it all was buying and installing those JB4 EWG add on connectors — which in essence is a super easy install…and yet I feel like there should be more venting on this board about connecting those suckers assuming you’re someone like me who spent hours sticking their hands through tight engine spaces bc they didn’t remove engine parts for a clearer pathway. But I digress…

My Stinger is also my daily driver and while the gas mileage isn’t ideal (of course partially bc how I drive!) it always is so worth it to me bc it’s such a fun cruiser and bruiser that puts a smile on my face. And I like how loud it is.

Do you get anypo420 codes….. or have you figure out a permanent fix for the overboost

 

[PMR818]

Do you get anypo420 codes….. or have you figure out a permanent fix for the overboost

Overboost has actually been frustrating the hell out of me more and more lately. I have RWD and I recently discovered another thread here where other RWD Stingers get overboost (and then limp mode) when accelerating and hitting a bump on the road or when losing traction.

But RWD specific issues aside, I’ll still overboost here and there on hard accelerations with just 91 pump on Map 2 — or with E30 on Maps 3 or 4 (I mean who knows what I’m getting at the E85 pumps and I don’t know if I’m putting too much or too little - I stick to 4-6 gallons). Terry from BMS recently told me to lower the FF in the JB4 by increments of 5 until the issue doesn’t persist. Mind you, I haven’t shared a log here in forever and I know nothing of the other settings in the JB4 to adjust; but I’ve been meaning to learn more.

Just yesterday the yellow check engine light came on for the first time and car went into limp. Today (engine light still on) I put the JB4 on Map 0 and I got some fun boost back (presumably from my pipes and intake). But I still managed to overboost into limp lol

 

[cncBilly]

Ah, sounds like the JB4 + the EWG cables are basically a prerequisite before you add the Ultimate Performance down and mid combo.

From everything I’ve read, I would agree with that statement.

 

[Omari1996]

Overboost has actually been frustrating the hell out of me more and more lately. I have RWD and I recently discovered another thread here where other RWD Stingers get overboost (and then limp mode) when accelerating and hitting a bump on the road or when losing traction.

But RWD specific issues aside, I’ll still overboost here and there on hard accelerations with just 91 pump on Map 2 — or with E30 on Maps 3 or 4 (I mean who knows what I’m getting at the E85 pumps and I don’t know if I’m putting too much or too little - I stick to 4-6 gallons). Terry from BMS recently told me to lower the FF in the JB4 by increments of 5 until the issue doesn’t persist. Mind you, I haven’t shared a log here in forever and I know nothing of the other settings in the JB4 to adjust; but I’ve been meaning to learn more.

Just yesterday the yellow check engine light came on for the first time and car went into limp. Today (engine light still on) I put the JB4 on Map 0 and I got some fun boost back (presumably from my pipes and intake). But I still managed to overboost into limp lol

Hey man so I know this is a way late response im just now seeing this thread and im sure you already have it figured out but just incase i was having the same exact issue. i got a 2019 GTS Snorkels, denso 2 step, BMS intakes, Jb4 Map 5 e30 and 93 pump. just purchased and waiting on my HFC downpipe + midpipe and stillen exhaust. but yea when I was having the issue i didnt have the fuel wires hooked up cause i was advised not to. but then when i added em and i never had overboost, a CEL, or Limp again. I run 5 GALs of e85 and the rest 93. and she runs beautifully,

 

[PMR818]

Hang on a smidge, so I should add the fuel wires add-on to my JB4 (Bluetooth)? I’ll friggin do it if so. Just assumed my EWG add-on connectors would solve all (if not most) the overboost. But I’m open to any-everything to help eliminate overboost. Also anything to help her sound less angry/raspy at times!

Hey man so I know this is a way late response im just now seeing this thread and im sure you already have it figured out but just incase i was having the same exact issue. i got a 2019 GTS Snorkels, denso 2 step, BMS intakes, Jb4 Map 5 e30 and 93 pump. just purchased and waiting on my HFC downpipe + midpipe and stillen exhaust. but yea when I was having the issue i didnt have the fuel wires hooked up cause i was advised not to. but then when i added em and i never had overboost, a CEL, or Limp again. I run 5 GALs of e85 and the rest 93. and she runs beautifully,

 

[Omari1996]

Hang on a smidge, so I should add the fuel wires add-on to my JB4 (Bluetooth)? I’ll friggin do it if so. Just assumed my EWG add-on connectors would solve all (if not most) the overboost. But I’m open to any-everything to help eliminate overboost. Also anything to help her sound less angry/raspy at times!

Yea so my fuel wires already came connected to the JB4 just possy tap them to the red wires on the o2 sensor. I’m sure you can find a video on YouTube that’s a little more specific

 

[Brichinelo]

Ah, sounds like the JB4 + the EWG cables are basically a prerequisite before you add the Ultimate Performance down and mid combo.

Or at least the ewg wires at minimum to keep those afr levels stable. I was also looking into this kit but was pushed away by overboost issues. The ewg wires paired with gapped spark plugs should be sufficient but that’s me taking stab at it. Also supporting mods as well…. Spark plugs, intercooler, intakes, exhaust

 

[Wongus]

Ewg add on will solve the overboost issues!

 

[PMR818]

EWG add on has indeed eliminated almost all overboost ever since I installed last year. And I can't stress enough - like a broken record - how much of a PAIN it was unlocking the stock connectors and then plugging in the add on connectors unless you have child hands that can go thru ultra tight spaces. Having mods in the way prob didn't help as well (I don't know how the hell to take out parts in the way like my intakes and put them back in!)

Anyways us RWD Stingers have some unique overboost circumstances tho (like hitting bumps in the road while accelerating or shifting). After EWG install, I did have to mess with the FF in the JB4 settings to help bigtime as well. If anyone else has other JB4 settings to mess with, I'm always listening bc I like messing with numbers (with caution, no lectures pls).

 

[G-328020]

Hey StingerMG,

The Ultimate Performance HFC Downpipe Combo Kit requires a tune in order to work correctly.

Also, this is currently the only available combo kit that does not throw a CEL.

I hope this helps clear things up. ​

I have the JB4, will I still need a tune?

 

[alex_man120]

I have them and I'm on the lap3 ecu tune. I'm happy with the set up.

 

[Daniel @ K8 Stinger Store]

I have the JB4, will I still need a tune?

Nope, the JB4 is sufficient!