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Tuning JB4 Installation

How do you like it so far? Very interested in your thoughts.

I mean I love it. Installing was pretty easy, didn't take much time and don't need a professional to do it. The price to performance increase I think is probably the best you can get. Works great on stock parts. You can pull it out before a service if you're worried about your warranty and the dealer won't suspect a thing. I recommend it to anyone that wants to squeeze some cheap and easy performance out of their car.
 
Does anyone know if you can use the data cable to connect to a MacBook ? I liked the idea of running the Bluetooth dongle due to simplicity but also question it’s accuracy. However sadly I only own apple products and am a bit reluctant to buy a windows laptop just to tune my car.
 
I believe the app is available for Macs as well. Regarding the bluetooth accuracy, I've never had any issues with mine so far in terms of accuracy or making adjustments. I've compared log files on both my PC using the JB4 app and my phone and they're identical.
 
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Does anyone know if you can use the data cable to connect to a MacBook ? I liked the idea of running the Bluetooth dongle due to simplicity but also question it’s accuracy. However sadly I only own apple products and am a bit reluctant to buy a windows laptop just to tune my car.

https://www.n54tech.com/forums/showthread.php?t=21742

Just scroll down on the first post there is a JB4 OSX section near the bottom of the first post. And yeah what 1Fast said. The bluetooth is quite good so I don't think accuracy will be a major issue if you go that route.
 
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Disappointed that the BMS cable only results in 0.25s logging resolution. Unacceptable for a hardwired solution.

Not ready to give a review just yet as I’m still waiting on some slight config changes (fuel & plugs).

As far as Apple OSes or even linux, you could either stand up a win VM or use Wine.
 
Anybody using this notice any adverse increase in torque steer? I had a jb1 on a Golf R, but since it was AWD, it didn't affect steering at all. I'm more nervous about it on a FWD car, but maybe the lsd takes care of it enough?
 
Anybody using this notice any adverse increase in torque steer? I had a jb1 on a Golf R, but since it was AWD, it didn't affect steering at all. I'm more nervous about it on a FWD car, but maybe the lsd takes care of it enough?

Torque steer is increased from my experience. There is no getting around that. The LSD does it's job but as far as I can tell it's additive with the increase in power. This is completely baseless, I have done no real testing between stock and JB4 to measure the torque steer, but in my case with a car like this the more power you apply the more torque steer you get. I've noticed going WOT out of a corner my car likes to drift real hard to one side. It's certainly controllable if that helps as this situation was engineered for from the factory. It's never gone out of my control but I do know it's going to happen and I do try and compensate for it. I do kinda of wish the car was awd or at least rear wheel but honestly I don't have much of an issue with that as it is what it is.
 
Initial feedback is thus. Do not even think about getting this if you won’t consider replacing the factory spark plugs. Even after regapping them to .028” and end gapping them as well, I was getting audible knock that was not being recognized as misfires on map 2 and sometimes on map 1.

Swapped to colder plugs (0.023”) last night and now starting to work on creating a custom map6.
 
@Cygnus X-1
which spark plugs do you use?
R2556G-9

Been using these on the VT1 for years. They’re a little more expensive than the M45XL, but are very stout and laugh at high boost, E85, methanol, etc. Just have to do Italian tuneups more often to clean them up.

Don’t skimp on plugs. I would never run the Denso plugs they mention.
 
Does anyone have real world test numbers? 0-60/100mph times compared to stock? I have been running track cars for many years and stop tunning engines becuase it was not manifesting improvements on track time. I am on the fence for a tune unless there is some hard evidence. Dyno numbers are just a tuning tool. I would like real world data. I am going to set some baselines this weekend since the 400mile bip is completed. I am looking at a set of 18 inch track wheels weighing 18lbs a wheel. Dont know how much the stock pp wheel weighs but I expext at least 10lbs loss in rotational mass. That is huge! The biggest difference in the R from a base 350 was the wheels. The CF wheels turned the R into a car God lol
 
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Does anyone have real world test numbers? 0-60/100mph times compared to stock? I have been running track cars for many years and stop tunning engines becuase it was not manifesting improvements on track time. I am on the fence for a tune unless there is some hard evidence. Dyno numbers are just a tuning tool. I would like real world data. I am going to set some baselines this weekend since the 400mile bip is completed. I am looking at a set of 18 inch track wheels weighing 18lbs a wheel. Dont know how much the stock pp wheel weighs but I expext at least 10lbs loss in rotational mass. That is huge! The biggest difference in the R from a base 350 was the wheels. The CF wheels turned the R into a car God lol
I'm sure there is a reduction in 0-60mph from stock.
On my G70, I went from 6.0sec to 5.5secs on a custom Map6. I'm much more limited than you guys. You have a better turbo and exhaust setup!
 
No comparison really, as the Genesis G70 is way to heavy for the 2.0T. Veloster N is much lighter, FWD, electronic LSD etc.

0-60 times vary from driver to driver.
 
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No comparison really, as the Genesis G70 is way to heavy for the 2.0T. Veloster N is much lighter, FWD, electronic LSD etc.

0-60 times vary from driver to driver.
I'm not comparing. I'm saying that if I can reduce my 0-60 time, there's no reason the VN can't with all the extra advantages it has!
 
Didn't say you were I did. You're in an automatic and which makes quite a bit of difference. The G70 has now way to bring up rpms for a good launch, except to power brake. Most of the time this hurts a launch.

Driver dependent always! If the driver can't launch the car with a manual transmission, it won't make any difference.
 
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Doesn't work, both the Stinger and the G70 is rear wheel drive. E-brake is piggy backed on the the rear brakes. It's just a problem with any DCT or standard automatic.
 
Found this on YouTube and it does a good job of explaining how to install the Bluetooth dongle in the jb4. I know it’s for a biemmer but still relevant.

 
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