[abirmaher]

Hi All,

I just installed a Burger Motorsports JB4 in my 2024 X1 M35i. I purchased this a few weeks ago and had to reach out to them as the included harness did not work for this platform. I ended up keeping the JB4 in my airbox while we got this sorted out, but have been using it for a few weeks without issue. Their support has been great, as it always is and they were able to get a new wiring harness out to me that did work which I installed this past weekend. If you plan to order, I suggest you reach out first and hopefully, they can include the correct harness for you.

https://burgertuning.com/products/bm...gen3-jb4-tuner

I was not able to find any great set of instructions out there for installing the JB4 on out transverse mounted B48, Mini based, platform. The installation guide for the product website above applies to the B58 and B48 and not the transverse-mounted configuration. The guide for installing the Mini version was also not super helpful. So I figured I would throw a video together for anyone interested.

I did some logging on Map 1 and 2 and through I run 93 octane fuel as is required for map 2, I was told map 1 was what I should be running for now. It seems that the M35i engine tuning is already a bit on the aggressive side so adding even 3-4 PSI pushes it to quite high boost numbers. Burger told me that they would need to add some additional logging channels before suggesting I move to Map 2.

Initial Driving Impressions: As I mentioned, I am only on Map 1 and honestly it is not a massive difference. At least not my initial impression at least. I will try and do some better comparisons eventually but for now, it may give just a bit more poke but nothing huge to write home about. Keep in mind I only have a cold air intake in terms of other supporting mods, so there may be more room with a downpipes installed or other similar mods.

The gauges and logging is a nice feature but again, not something I see needing or using very often at all.

Overall, I am not sure if it is worth it just yet. Just my take, but feel free to pick one up and form your own thoughts and report back.

[BabyX6]

I appreciate the video!

So, my JB4 kit came also with a fuel rail sensor. It doesn't seem that yours did?

[abirmaher]

Originally Posted by BabyX6

I appreciate the video!

So, my JB4 kit came also with a fuel rail sensor. It doesn't seem that yours did?

Hello! So mine did originally. But when I tried to fit it, it turned out that due to the transverse mounting of our engines, the harness did not fit (lengths of the 2 plugs I installed were flipped). I worked with the support team at Burger and they were able to send me another harness where the lengths of the harness plugs worked better for our platform.

With regard to the fuel rail sensor, I was told that as of now it had not been tested for use on this platform so it was not needed. It can just be plugged into itself and tucked away. But when they sent me the revised harness, they just removed it altogether.

I would suggest you lay out your harness over the engine bay and see if the plugs seem to be long enough to reach where they need to, and if not you may not have the correct harness and support may need to send out a new one to you.

Hope this helps!

[BabyX6]

Originally Posted by abirmaher

Hello! So mine did originally. But when I tried to fit it, it turned out that due to the transverse mounting of our engines, the harness did not fit (lengths of the 2 plugs I installed were flipped). I worked with the support team at Burger and they were able to send me another harness where the lengths of the harness plugs worked better for our platform.

With regard to the fuel rail sensor, I was told that as of now it had not been tested for use on this platform so it was not needed. It can just be plugged into itself and tucked away. But when they sent me the revised harness, they just removed it altogether.

I would suggest you lay out your harness over the engine bay and see if the plugs seem to be long enough to reach where they need to, and if not you may not have the correct harness and support may need to send out a new one to you.

Hope this helps!

Thank you for the quick and thoughtful response!
So ultimately my JB4 black box itself is sitting perched right next to the red/positive battery terminal cap at that flat area that sits right under the stabilizer bar. If it were any further away, the TMAP harness wouldn't have made it. With it positioned there, the harness to the MAP and even to the fuel rail were perfect. I do however wish I could have stored the black box inside the weatherproofed cowl barrier. But I'm not certain I need to fear for it sitting where it is either?

I ultimately plugged the fuel rail sensor harness in, only to discover on my own that it wasn't functional as the car ran like shit. The CEL went back off on its own today.

Apparently my Android 15 is not allowing me to email my logs as the app itself isn't playing nice with 15, so tomorrow I'll be reflashing 14. Regardless of that, my Map 1 has produced a seat of the pants improvement that I noticed while taking a couple logs at 40-90mph. I had noticeable torque steer during most of my acceleration, making it feel loosey goosey.

How long has yours been in place? Thoughts?

I'm very glad you posted this video! Thank you for taking the time! Saved my butt.

[abirmaher]

Originally Posted by BabyX6

Thank you for the quick and thoughtful response!
So ultimately my JB4 black box itself is sitting perched right next to the red/positive battery terminal cap at that flat area that sits right under the stabilizer bar. If it were any further away, the TMAP harness wouldn't have made it. With it positioned there, the harness to the MAP and even to the fuel rail were perfect. I do however wish I could have stored the black box inside the weatherproofed cowl barrier. But I'm not certain I need to fear for it sitting where it is either?

I ultimately plugged the fuel rail sensor harness in, only to discover on my own that it wasn't functional as the car ran like shit. The CEL went back off on its own today.

Apparently my Android 15 is not allowing me to email my logs as the app itself isn't playing nice with 15, so tomorrow I'll be reflashing 14. Regardless of that, my Map 1 has produced a seat of the pants improvement that I noticed while taking a couple logs at 40-90mph. I had noticeable torque steer during most of my acceleration, making it feel loosey goosey.

How long has yours been in place? Thoughts?

I'm very glad you posted this video! Thank you for taking the time! Saved my butt.

Glad to hear all of that. I preferred mine behind the cowl but I think it would not have reached if I hadn’t swapped that harness. And the fuel rail sensor issue you faced makes sense as they told me they had not yet tested or used it on this model.

I have had it on for a few months but to be honest I need to turn it back off to see if I notice a difference. I think I will but it’s been so long that I don’t really recall feeling a massive change.

I need to do that and have a little follow up write up.

[BabyX6]

Originally Posted by abirmaher

Glad to hear all of that. I preferred mine behind the cowl but I think it would not have reached if I hadn’t swapped that harness. And the fuel rail sensor issue you faced makes sense as they told me they had not yet tested or used it on this model.

I have had it on for a few months but to be honest I need to turn it back off to see if I notice a difference. I think I will but it’s been so long that I don’t really recall feeling a massive change.

I need to do that and have a little follow up write up.

Another question friend!

So I noticed my map was being switched to 8 after making those WOT runs. Did a search, learned that it'll do you that if you hit the boost limiter as a safety mechanism. I found the setting in the app, it was set to 25.9 (presumably set by Burger). I checked the logs, I had a peak boost registered at 26.5.

I've emailed Burger for education and advice about simply raising the limiter by a pound. But what say you? What's your limiter set to and have you hit it? What's the max boost you've recorded? Assuming yours is also set to 25.9, do you know if 25.9 was set strictly? Like setting it to 26.9 may throw a rod or put a hole in a piston?

After continuing to observe the car's acceleration with map 1, this thing seriously shits and gits. Feeling the torque steer in a straight line is really something. It also sounds more pissed off. And I'm not sure if this thing has a blow off valve, but I literally heard the turbo vent today when I let off WOT.

[abirmaher]

Originally Posted by BabyX6

Another question friend!

So I noticed my map was being switched to 8 after making those WOT runs. Did a search, learned that it'll do you that if you hit the boost limiter as a safety mechanism. I found the setting in the app, it was set to 25.9 (presumably set by Burger). I checked the logs, I had a peak boost registered at 26.5.

I've emailed Burger for education and advice about simply raising the limiter by a pound. But what say you? What's your limiter set to and have you hit it? What's the max boost you've recorded? Assuming yours is also set to 25.9, do you know if 25.9 was set strictly? Like setting it to 26.9 may throw a rod or put a hole in a piston?

After continuing to observe the car's acceleration with map 1, this thing seriously shits and gits. Feeling the torque steer in a straight line is really something. It also sounds more pissed off. And I'm not sure if this thing has a blow off valve, but I literally heard the turbo vent today when I let off WOT.

Very interesting! Let me know what they say, I have not seen that myself. But I have not been looking for that to be honest.

[abirmaher]

Follow Up Post

Hi all, after running the JB4 for a few months I don't even really think about it which is why this post has taken so long. I tried switching maps and even turning it off to see if I feel any difference. To be honest, I don't really feel much change.

I am not sure if I am running into some sort of safety but comparing Map 0 (JB4 Off), Map 1 (Stock +3 PSI) and Map 2 (Stock + 4PSI), I don't feel much difference. Burger did suggest that I stay on Map 1 as the tuning on the M35 is already aggressive from factory, the boost was getting a bit too high for their comfort.

Ultimately, I can't say that this is a justifiable mod for the M35 variant, but I think it would make a much bigger impact on any of the other trim levels that have similar engines but are detuned. Just my thoughts.

Here is a comparison video from this morning:

[abrandonment]

Super helpful information. I'm bummed it isn't a bigger difference but in a way almost relieved..

[abirmaher]

Originally Posted by abrandonment

Super helpful information. I'm bummed it isn't a bigger difference but in a way almost relieved..

That said mine may be for sale soon… if you want to try it yourself…

But like I said, I think it’s better for the non M35 cars.

[BabyX6]

I was lucky to buy mine w/ Bluetooth adapter, used off this board. To be honest, I wasn't willing to pay full price and I would tell anyone the same: don't spend $850 retail, the value is far from being there.

I do appreciate the ability to observe things like Boost and AFR. I do appreciate the ability to log those things and have Burger willing to evaluate and recommend. I do appreciate the built-in code reader and the ability to clear codes. Considering my neurosis, I appreciate knowing that I've maxed out the engine's capabilities, whether it feels significantly faster or not (not).

I personally feel a slight improvement, but honestly only when the tranny is set to 'S'. The engine is also slightly louder, including the turbo. Tomorrow I'll go one small step further and make a logged run with it set to stock, so I can observe the actual difference in boost. As I mentioned above, I've recorded a max boost of 26.5 on map 1. Doing some reading, older b48's maxed out at 22.

[abirmaher]

Originally Posted by BabyX6

I was lucky to buy mine w/ Bluetooth adapter, used off this board. To be honest, I wasn't willing to pay full price and I would tell anyone the same: don't spend $850 retail, the value is far from being there.

I do appreciate the ability to observe things like Boost and AFR. I do appreciate the ability to log those things and have Burger willing to evaluate and recommend. I do appreciate the built-in code reader and the ability to clear codes. Considering my neurosis, I appreciate knowing that I've maxed out the engine's capabilities, whether it feels significantly faster or not (not).

I personally feel a slight improvement, but honestly only when the tranny is set to 'S'. The engine is also slightly louder, including the turbo. Tomorrow I'll go one small step further and make a logged run with it set to stock, so I can observe the actual difference in boost. As I mentioned above, I've recorded a max boost of 26.5 on map 1. Doing some reading, older b48's maxed out at 22.

Agreed. I bought mine on here used as well. I wasn’t willing to spend the 850 either.

All of those benefits are nice but things I can happily live without.

My suggestion is to get the intake from burger and enjoy the turbo noises and not spend the money on this. But again I do think other models that are not the M35 which is essentially already maxed out will feel more benefits.