MT Supra JB4

[Deleted member 10795]

Anyone have JB4 on their MT? If so how is it? Ive been hearing that it doesnt work properly on the manuals, is this true?

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[ZokiSpeed]

Hey Jordan, it's not exactly the thing/answer you're searching for, but i was really disappointed from the JB4-Kit on my 2021 2.0L EU-Version.
It's an AT, but it still completely changed the behaviour of the transmission too: throttle response, downshifting, manual shifting. It just doesn't work good. Here in germany the fuel should be good, but it just didn't work properly. -I was really disappointed. So i switched to a custom map from a local dealer and the car feels good again. Everything feels like OEM, but with much more power.
Will post in the next days in my thread a dyno-sheet from the JB4-kit on the 2.0L...
The only good thing was, that the hp specification was correct. It made exactly 300hp, as quoted. But you'll laugh if you see at which rpm the 300hp were available.
So in my opinion the price isn't justified. Maybe it's not that pricey in US (here in germany 850$) but still...

 

[zrk]

Hey Jordan, it's not exactly the thing/answer you're searching for, but i was really disappointed from the JB4-Kit on my 2021 2.0L EU-Version.
It's an AT, but it still completely changed the behaviour of the transmission too: throttle response, downshifting, manual shifting. It just doesn't work good. Here in germany the fuel should be good, but it just didn't work properly. -I was really disappointed. So i switched to a custom map from a local dealer and the car feels good again. Everything feels like OEM, but with much more power.
Will post in the next days in my thread a dyno-sheet from the JB4-kit on the 2.0L...
The only good thing was, that the hp specification was correct. It made exactly 300hp, as quoted. But you'll laugh if you see at which rpm the 300hp were available.
So in my opinion the price isn't justified. Maybe it's not that pricey in US (here in germany 850$) but still...

JB4 doesn't have the ability to change shift points, but yes, the factory maps are garbage.

 

[ZokiSpeed]

JB4 doesn't have the ability to change shift points, but yes, the factory maps are garbage.

I know that, I didn't mean that it changed the shift points. I mean that the torque maps didn't seem to match with the gearbox software or the gearbox software seems to expect a different behaviour from the engine... I stepped slowly on the gas and it switched the gears frequently with no sense. Sometimes at the traffic light i stepped on the gas and nothing happened for a second. Then it wents from zero to hundred percent gas, even though i haven't been on the gas that hard. It feeled laggy and strange. Can't describe it better.

 

[Cfdproductions]

will report back ... working on this with Jesse or just follow my build page and I will for sure be leaving info on this good or bad

 

[i3igpete]

Sometimes at the traffic light i stepped on the gas and nothing happened for a second. Then it wents from zero to hundred percent gas, even though i haven't been on the gas that hard. It feeled laggy and strange.

There is a thread in the UK section about this weird hesitation where it lags and then has a sudden hard acceleration, but it doesn't seem to affect US cars. If the German cars also have an OPF, you might be having the same calibration issues. Some Uk members have reported smoother low-speed drivability after getting an update, but the problem is convincing their dealer to do it

 

[Isaleus]

https://www.supramkv.com/threads/manual-tuning-options.21220/#post-343945

 

[jtsang25]

There is a thread in the UK section about this weird hesitation where it lags and then has a sudden hard acceleration, but it doesn't seem to affect US cars. If the German cars also have an OPF, you might be having the same calibration issues. Some Uk members have reported smoother low-speed drivability after getting an update, but the problem is convincing their dealer to do it

Definitely affects North American cars. There's a thread for throttle hesitation.

 

[puzzled]

I've been running JB4 on my 2020 since like a week after inception. Works flawlessly including the BT module.. I've trialed the maps (1 & 2) back to back with 0 and at least on my 2020, it only adds more power and it's smooth.

My car is still capable to be flashed.. but for me, JB4 is plenty.

Why I chose JB4 was because I was running their piggy backs on my GTI and Golf-R with much success. I got a Cobb flash for my R about 3 yrs ago. GTI was sold.

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