GR Yaris JB4 box

Onehp

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And my question: has anybody actually gotten one?
Much of JB4 is about the community but haven't heard of a single one...
 

MRA3

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Dec 29, 2021
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I haven’t heard of anyone either. Does this box have any different working principle from others? Say DTUK or similar?

Being a US brand, and given the GR is not officially sold there is probably the reason why this isn’t popular yet. They first question would be how they have developed something for a car that isn’t sold in the States…
 

Onehp

Totally Hooked
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I haven’t heard of anyone either. Does this box have any different working principle from others? Say DTUK or similar?
Like most boxes it interferes with the boost signal. However it is the only one that uses OBD/canbus data as input. It can also do good logging via an app via Bluetooth, and one can make ones own custom boost map.

These are the features I like, but at the same time not very interested in being a Guinea Pig for this platform in case it doesn't work as intended...

I have experience with JB4 on a VAG group car, and there it also intercepts fuel and the AFR O2 sensor, not so here

DTUK v2 is of some interest with intercepting the MAF signal, potentially making it a bit safer, but I'm the kinda person that wants to know what it actually does (with normal logging one can't see much, such is the nature of a piggyback...)
 
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MRA3

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Dec 29, 2021
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Like most boxes it interferes with the boost signal. However it is the only one that uses OBD/canbus data as input. It can also do good logging via an app via Bluetooth, and one can make ones own custom boost map.

These are the features I like, but at the same time not very interested in being a Guinea Pig for this platform in case it doesn't work as intended...

I have experience with JB4 on a VAG group car, and there it also intercepts fuel and the AFR O2 sensor, not so here

DTUK v2 is of some interest with intercepting the MAF signal, potentially making it a bit safer, but I'm the kinda person that wants to know what it actually does (with normal logging one can't see much, such is the nature of a piggyback...)
I agree and personally not sure how healthy for the engine those boxes are long term. And as you say, difficult to understand how the engine is really running with one plugged in.

It looks like the JB4 could be a better overall package, but the actual development is a question mark.
 
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prx_chain

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Feb 23, 2022
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I haven’t heard of anyone either. Does this box have any different working principle from others? Say DTUK or similar?

Being a US brand, and given the GR is not officially sold there is probably the reason why this isn’t popular yet. They first question would be how they have developed something for a car that isn’t sold in the States…
I think the development is being done together with Evolve/Eventuri in the UK
 
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Onehp

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Update.

Me and a friend went ahead and ordered one each.
Little bit ironic perhaps in a time when quite a few will dump their boxes for a remap.

At the same time, further on the horison there is now a confirmed possible future for it with the GRC coming to the US, a car running a bit more top end boost from factory, something the JB4 allows to mimic with its custom map 6 features.

Anyhow, we'll see when it arrives (can take some time...) and of course will update on our findings.
 

MRA3

Dedicated member
Dec 29, 2021
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Update.

Me and a friend went ahead and ordered one each.
Little bit ironic perhaps in a time when quite a few will dump their boxes for a remap.

At the same time, further on the horison there is now a confirmed possible future for it with the GRC coming to the US, a car running a bit more top end boost from factory, something the JB4 allows to mimic with its custom map 6 features.

Anyhow, we'll see when it arrives (can take some time...) and of course will update on our findings.
Why did you guys choose the JB4 vs a remap? Interested to understand it, because it’s a questions you must have asked yourselves -if you bought it after the ecu announcement was made, of course-
 

SW230

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Dec 16, 2021
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Burger Tuning who produce the JB4 and the JB+ products have a worldwide following in the BMW market (+ other makes). I have previously used the JB+ module on my M240i BMW and was very impressed. I am interested in following this thread as the JB4 could be an excellent option for our GRs.
 

GR MJR

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Dec 31, 2021
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Will keep a keen eye on how you do with it.
I think ill go the jb4 route now America is going to get the GRC.

Keep us in the loop with how you find it
 
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Onehp

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Yeah will report how we find it.

Why did you guys choose the JB4 vs a remap?
Like others we have previous good experience with JB1/JB4. The one on the Yaris is more simple but there is at least a future for it now with the GRC coming to BMS headquarters (until then it's Beta).

Reasons to go for JB4 vs remap is mainly that we have own control:
- possibility to tune to our own mind, tune differently for season or event. E. g. we deeply dislike heat soak so we can turn down boost so it works for our driving/hardware, rather then it cutting when things get too much fun...
- no need to rely on tuner with trips, time and £€$ if changing something (if you have a great tuner on your doorstep, that's something else)
- simple to put back to standard and resellable
- we will 'leave some power on the table' but we're ok with that, we're more interested in changing the subjective driving experience and making adjustments for hardware improvements.
- as more features come available later it might be possible to add more power if one wishes so.
- obviously if one is going far beyond OE power levels, remap or even standalone ECU are better

Vs other boxes:
- possibility to finetune for our own (changing?) hardware
- logging that is not skewed by the box
- have own approach how to deal with cars limitations: high lambda sub 4k rpm and with general high heat
- not just adjust general power level but also possible to change power delivery

All the above based on easy logging that is inbuilt in the JB4 + app, we'll see what can be logged and be added.
 
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Onehp

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First one arrived with my friend


283774961_539564507702981_4459232998851380443_n.png

Now with MAF sensor intercept


281611676_728582868318932_2768845293405988022_n.jpg

Install OBD cable

281517551_370902535098886_2273205946937755926_n.jpg

Invisible when using OBD splitter that replaces the original OBD plug


281587947_393139376074983_6386294092829831024_n.jpg

Not so invisible but possible to remove in 5-10min

280960574_303859931959601_5285905962066020768_n.jpg

Cool JB4 mobile app


Logging is not so great, all temps are missing, no ignition retardation, hoping to add those later. Also scaling seems to be off...

Running map 1 didn't go so well, they seem to be to aggressive, but a custom map 6 seems to have effect, this is the main point for us, we can put in boost where we find works well for our hardware (HJS + IC) and tastes. Not getting much wise from the logs though, so it's very much Beta at this stage unless we missed something...

To be updated...

Edit 1: new firmware was available, let's see how that goes.
 
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Onehp

Totally Hooked
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We already got 2nd firmware today, new MAF signal allows to bias AFR but still in Beta, learning...
Good support and this will develop in the coming time... Honestly we rather have something finished obviously but if progress is swift then it's ok...
 
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