Who is Running Catless? What Temps Are You Seeing? What Tuner Box Are You Using?

I know you think I'm lying to you and an trying to be a dick but the jb4 isn't accurate when reading boost. 20psi won't cause the car to overboost. It takes allot more than that while you have a piggyback.
Map 0 is no added boosts map 2 I hit over 24 psi but I let off ss I know that's just too damn much boosts. I'm assuming it would have went up to 27 psi.
 
Maybe not, if as in your case temperature extremes play a part. One of the things I read today was that catalytic converters "work" to limit pollutants out the tailpipe only in a temperature range like coastal CA (I think I got that right): that colder temps reduce the cat's effectiveness to almost nil; but the law is the law. If you take the cats off and run really cold you are messing with the rest of an integrated system and courting trouble if not destruction of the engine.

No, I don't. A speed limiter and cat are hardly analogous. One is just an artificial cut out, the other integrates with the fuel and air mixture via computer. If you lobotomize the speed limiter, it only releases the engine to go as fast as it is designed. To remove a cat potentially risks computer readings, which can make the engine run hot and fry rings and such. (I'm possibly missing something in your analogy, but I think it's a false analogy.)
That analogy was in response to it was designed with the car therefore its needed. Same could be said about mufflers.
 
I know you think I'm lying to you and an trying to be a dick but the jb4 isn't accurate when reading boost. 20psi won't cause the car to overboost. It takes allot more than that while you have a piggyback.

I know its not 100% accurate but no ones is unless you have a vacuum boost reader. I do think 20 PSI is probably around were the they would set a limit to hit the overboost.
 
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Just a thought. Even though you are on Map 0 does the JB4 safety boost cut still stay active? That is set to 20 psi by default. I'd try disconnecting the JB4 completely just for a test.

That's a good thought. I may try that only downside I cant log anything.
 

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That analogy was in response to it was designed with the car therefore its needed. Same could be said about mufflers.
Not to belabor the point: but a speed limiter is like an "add on", not designed to go as an integral part of the design that determines how the car runs.

I'm still wondering why all you all modders feel driven to do this catless thing; to me the variables seem extant enough to make it risky. Why do risky things for minimal returns? So assume you get a noticeable boost to your car's performance and cool noise: if the catless operation of the engine risks it (you're risking something or you wouldn't be concerned), why do you do it?
 
Not to belabor the point: but a speed limiter is like an "add on", not designed to go as an integral part of the design that determines how the car runs.

I'm still wondering why all you all modders feel driven to do this catless thing; to me the variables seem extant enough to make it risky. Why do risky things for minimal returns? So assume you get a noticeable boost to your car's performance and cool noise: if the catless operation of the engine risks it (you're risking something or you wouldn't be concerned), why do you do it?
If you are content with your cars performance good for you, but there are a plenty of us that want to pull out more from the car. Again I've said this already but going catless is not something new. It has been done for a long time in performance cars.
 
If you are content with your cars performance good for you, but there are a plenty of us that want to pull out more from the car. Again I've said this already but going catless is not something new. It has been done for a long time in performance cars.
I didn't think it was a new thing: I've seen thread titles for months by now, and removing the catalytic converter is something I had heard about years ago but never paid any attention to. I appreciate why you want more out of a car that starts out delivering as much as the GT does. But the risk of removing the cat from a modern car that depends on it to keep the computerized fuel and air mixture correct is what I don't understand. If it is risky, and even more so on today's cars, why do it in the first place? I don't get it.

Let me make an analogy: nitrous boost is okay in a race car engine for that temporary, risky speed advantage; but would you run it in a street car, a daily driver that you are modding to go faster? It'll destroy the engine. Race car teams operating on a big budget probably count the hazards and shortened engine life as part of the costs to be competitive. But having a faster car via nitrous is just plain stupid for a street machine, unless you don't really care. Which is what I don't get.
 
I didn't think it was a new thing: I've seen thread titles for months by now, and removing the catalytic converter is something I had heard about years ago but never paid any attention to. I appreciate why you want more out of a car that starts our delivering as much as the GT does. But the risk of removing the cat from a modern car that depends on it to keep the computerized fuel and air mixture correct is what I don't understand. If it is risky, and even more so on today's cars, why do it in the first place? I don't get it.

Let me make an analogy: nitrous boost is okay in a race car engine for that temporary, risky speed advantage; but would you run it in a street car, a daily driver that you are modding to go faster? It'll destroy the engine. Race car teams operating on a big budget probably count the hazards and shortened engine life as part of the costs to be competitive. But having a faster car via nitrous is just plain stupid for a street machine, unless you don't really care. Which is what I don't get.

Welcome to the world of a performance car. That's why running a car catless is generally required to do so with a tune, or a piggyback that can modify afr. To you next analogy I have a nitrous 150 shot kit waiting to be put into this car once actual tuning for it is available. You dont modify your car unless you are willing to deal with the risks of doing so. You may not understand this as I'm sure you want to hold tight to your warranty and and dont care about taking your car or going to a drag strip. Again, there are those that do. This is really the wrong thread for you and it's just derailing what its purspose was for. Maybe start a why modify your car thread?

You would be shocked with the amount of street cars running NOS. It's not uncommon in the performance car scene.
 
@DaBears4Lyfe Looks like someone needs to ditch the the JB4 and get a Lap 3 pro tuner. LOL
Disclaimer: I AM JOKING EVERYONE, PLEASE JB4 FAN BOYS DONT ATTACK ME.

On a serious note, if you decide to get rid of the lap 3 primaries let me know buddy I will come pick them up.
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
@DaBears4Lyfe Looks like someone needs to ditch the the JB4 and get a Lap 3 pro tuner. LOL
Disclaimer: I AM JOKING EVERYONE, PLEASE JB4 FAN BOYS DONT ATTACK ME.


On a serious note, if you decide to get rid of the lap 3 primaries let me know buddy I will come pick them up.

Lol NO!!!!! I refuse to live with cats lol. Tunes are coming

Tork is so close to wrapping up stage 2

BTR in Glenview said theirs will be ready by the end of the month

Lap 3 should be done by 2025 :D jk should be done soon as well. I may have to ride out the slow life, but I'm not going back lol.
 
This is really the wrong thread for you and it's just derailing what its purspose was for. Maybe start a why modify your car thread?

You would be shocked with the amount of street cars running NOS. It's not uncommon in the performance car scene.
So, poor analogy, then. You've answered my question. Thanks. You're all performance mad!:D Risks be damned, full speed ahead. For as long as it lasts. And then build/mod another one. I'm done. I won't derail anymore. I promise (not here, anyway).
 
So, poor analogy, then. You've answered my question. Thanks. You're all performance mad!:D Risks be damned, full speed ahead. For as long as it lasts. And then build/mod another one. I'm done. I won't derail anymore. I promise (not here, anyway).

I'll say this Merlin. Theres a reason I have never kept a car past 3 years :)
 
It would be great if this thread contained facts, and is not the usual ECU tune vs piggyback fanboys fuckery

I've been taking to OP about this over last days. To help people understand this problem:
This is an issue with wastegate scaling on cars with electronic wastegates. WGDC is commanded by the ecu on its scaled map profile based on what duty cycle it thinks is going to need for a target torque/boost target.

The OEM mapping for EWG DC is profiled based on spool characteristics of the OEM DP and full Exhaust. Two things are happening here.
1. The cold air is denser so it makes more boost for a given wgdc. For example Air that is in the single digits F is 10% denser than even 32 degree temps. Meaning 10% more boost. The OEM iat modifier table usually accounts for this by dropping target boost for a given temp/airmass.
2. The full catless setup is making more boost, way faster for a given DC.

This is not the normal overboost suppression issue which piggy backs normally tackle easily by spoofing reported map signals back to ecu.

This is factory ecu commanding more DC than is actually required given the new spooling profile, thus overshooting it's " requested" torque/boost.

As far as I am aware, no current tuning solution either piggy back or flash tune can directly address the the root of the issue, which could only be addressed by either intercepting and directly controlling the ewg, or having access to the scaling tables for ewg control maps in the ecu.

What Jesse is asking in this thread is comments and feedback from
1. People who are catless
2. People who are in cold climates with DP
3. People who have both and are logging behaviors

I've had slightly similar issues, on occasion but only in initial spool, it levels out to normal levels of 19ish psi on map 3 jb4 in weather around 30-40 f. Given the snow and I live in the city, I've not had occasion to get hard runs in to see if I'm having the same level of issues that op is having. I'm going to try to get some runs in this -15 c weather and see what happens. Attached is screen cap of what we are discussing
 

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Warmer weather and a higher boost target setting in the piggy back will likely suppress the issue hence why people in warmer temps may not see it. But since the lap3/ flash tune guys don't have advanced logging they might not know it's even happening.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
Lol NO!!!!! I refuse to live with cats lol. Tunes are coming

Tork is so close to wrapping up stage 2

BTR in Glenview said theirs will be ready by the end of the month

Lap 3 should be done by 2025 :D jk should be done soon as well. I may have to ride out the slow life, but I'm not going back lol.
What BTR will be done by the end of this month?? That’s awesome. BTR is local to us ?
This is awesome what happened to that other shop you told me about? Have you thought taking your car to BTR?

Good luck man I hope you get it all sorted out by track season, so we can hit the track together.

I wonder that the Tork stage 2 is? Is that like a catless full bolt on tune?
 
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It would be great if this thread contained facts, and is not the usual ECU tune vs piggyback fanboys fuckery

It would be great if the whole community thought this way. Honestly looking at Facebook / some threads on here it's embarrassing how much hate there is for people running different tunes and other tuners bragging that literally everything else is trash because they can't match a Dragy time
 
Have maybe 20 JB4 cars running catless without issue. When there is an over boost issue that needs to be resolved it's 2-3psi not the 10psi+ OP is seeing, so I suspect he has a hardware issue like the WG arm movement is blocked or seized.

The JB4 is more advanced than all of the other piggybacks out including Lap3Pro and the JB4 can control WGDC directly in both banks. We do it on many BMW applications including the //M models. But we do not have that feature/wiring implemented on the Stinger yet. No other Stinger piggyback offers WGDC control. So if WGDC really needs to be dramatically reduced on this car the only way to do that currently would be to directly adjust the WGDC base tables in the flash/ECU itself.
 
Warmer weather and a higher boost target setting in the piggy back will likely suppress the issue hence why people in warmer temps may not see it. But since the lap3/ flash tune guys don't have advanced logging they might not know it's even happening.

This is a different issue than the usual 2-3psi over boost we see and can tune around using the JB4's IAT spoofing. I suspect one of his wastegates are physically blocked shut or something bizarre is going on. On stock tuning it's hitting 24psi at half throttle.
 
This is a different issue than the usual 2-3psi over boost we see and can tune around using the JB4's IAT spoofing. I suspect one of his wastegates are physically blocked shut or something bizarre is going on. On stock tuning it's hitting 24psi at half throttle.

Stock tunning its hitting 20 psi. Map 2 has hit 24 psi and Map 3 today hit 25 psi.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
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