335i JB4 Installation - A quick review / first impressions.
Discussion
Hello PH, I have had my 335i for around 3 months now, I think I would say that I'm now getting used to the car. Time for more power!
I researched on the web for a while on ways to improve the car and one thing seemed to stand out the most on my search. A JB4 (Juice Box 4) Stage 3 tuning box.
I'm no stranger to a remap, as my past 2 cars have both had them done. So I took the plunge and ordered a JB4 direct from the US of A. Delivery was 7 days wed-wed.
Cost was £326.79 for the JB4 (no USB cable option) thanks to a strong pound on the day I ordered. Once I had added my customs charges at this end (£29.74) the total cost was £356.53. I made sure to email them beforehand to ask them to reduce the declaration value for customs, which they did at $100.
While waiting on it arriving I watched the installation videos and read the pdf instructions end to end several times so I knew what I was doing. It looks complicated on paper, but it's not as hard as it looks.
Tools required for a 335i are.
1 X 8mm socket and ratchet
1 X small flat blade screwdriver (around 2-3mm blade)
And that's it.
Installation took me around an hour, although if I were to do it again I could do it quicker, I just went really slow and followed the instructions to the letter.
Around 4 pieces of trim need to be removed under the engine bay to get ECU access, and once you're in the tricky part is removing the sub-connectors from the main ECU harness, everything else is a breeze and the colour coded plugs from the JB4 kit make it idiot proof, you only need to make sure they connect to the cars harness the correct way round. After I had completed the steps I crossed my fingers and started the car. It fired up fine! I breathed a sign of relief and put the car back together again, it looks quite daunting with all those ECU wires exposed!
First drive: I took it easy for the first few miles to get the car up to temperature and took it to my favourite spot for planting the throttle.
Oh my f**king god! What have I done! the car shot forward like a scalded cat, my face lit up like a schoolkid in a sweetshop, and before I knew it I was into triple digits so I eased off. That's when I said a few expletives! It's hard to explain, but it feels like a whole new car.
I have no idea on other 335i's but mine when standard felt like it had a flat power curve all the way to the redline, now the turbos kick in sooner, and it pulls harder halfway up the rev range to the redline. The traction light shown itself in 3rd gear in the dry, it's never done that before. It's a very different beast now!
On the instructions it said it may throw a check engine light after the first few starts, and sure enough it did, a reduced power light came on. I switched the engine off and back on again, and it hasn't reappeared in over 200 miles since. Apparently this is normal due to ECU adaptation, but I'll keep an eye out for any further codes.
Gauge highjacking is a fun feature, I press the volume down and track down buttons together and I can change settings on the JB4. The gauges now become menus. 0mph = menu 0, 10mph = menu 1 etc. and the rev counter is the settings within that menu. I added gauge sweep and shift light for a while, but I got bored of them and set them back to standard settings. Added bonus is that when running any map, it disables the OBD port. So it should be safer from theft too. It can also be switched off via the wheel too for when I take the car to BMW for any service work. They recommend you remove it completely before putting it in for work, but to be honest, the only way they are going to find it is if the open the ECU cover and see it in there. And unless I'm going in for engine work, then I don't really see the need to remove it. My insurance premium increase wasn't too bad either.
For under £400, I think that's fantastic bang for buck. I'll look forward to the summer weather now, I feel I'm overwhelming my poor winter tyres.
If you're on the fence at all about getting your 335i remapped, then do it!
I researched on the web for a while on ways to improve the car and one thing seemed to stand out the most on my search. A JB4 (Juice Box 4) Stage 3 tuning box.
I'm no stranger to a remap, as my past 2 cars have both had them done. So I took the plunge and ordered a JB4 direct from the US of A. Delivery was 7 days wed-wed.
Cost was £326.79 for the JB4 (no USB cable option) thanks to a strong pound on the day I ordered. Once I had added my customs charges at this end (£29.74) the total cost was £356.53. I made sure to email them beforehand to ask them to reduce the declaration value for customs, which they did at $100.
While waiting on it arriving I watched the installation videos and read the pdf instructions end to end several times so I knew what I was doing. It looks complicated on paper, but it's not as hard as it looks.
Tools required for a 335i are.
1 X 8mm socket and ratchet
1 X small flat blade screwdriver (around 2-3mm blade)
And that's it.
Installation took me around an hour, although if I were to do it again I could do it quicker, I just went really slow and followed the instructions to the letter.
Around 4 pieces of trim need to be removed under the engine bay to get ECU access, and once you're in the tricky part is removing the sub-connectors from the main ECU harness, everything else is a breeze and the colour coded plugs from the JB4 kit make it idiot proof, you only need to make sure they connect to the cars harness the correct way round. After I had completed the steps I crossed my fingers and started the car. It fired up fine! I breathed a sign of relief and put the car back together again, it looks quite daunting with all those ECU wires exposed!
First drive: I took it easy for the first few miles to get the car up to temperature and took it to my favourite spot for planting the throttle.
Oh my f**king god! What have I done! the car shot forward like a scalded cat, my face lit up like a schoolkid in a sweetshop, and before I knew it I was into triple digits so I eased off. That's when I said a few expletives! It's hard to explain, but it feels like a whole new car.
I have no idea on other 335i's but mine when standard felt like it had a flat power curve all the way to the redline, now the turbos kick in sooner, and it pulls harder halfway up the rev range to the redline. The traction light shown itself in 3rd gear in the dry, it's never done that before. It's a very different beast now!
On the instructions it said it may throw a check engine light after the first few starts, and sure enough it did, a reduced power light came on. I switched the engine off and back on again, and it hasn't reappeared in over 200 miles since. Apparently this is normal due to ECU adaptation, but I'll keep an eye out for any further codes.
Gauge highjacking is a fun feature, I press the volume down and track down buttons together and I can change settings on the JB4. The gauges now become menus. 0mph = menu 0, 10mph = menu 1 etc. and the rev counter is the settings within that menu. I added gauge sweep and shift light for a while, but I got bored of them and set them back to standard settings. Added bonus is that when running any map, it disables the OBD port. So it should be safer from theft too. It can also be switched off via the wheel too for when I take the car to BMW for any service work. They recommend you remove it completely before putting it in for work, but to be honest, the only way they are going to find it is if the open the ECU cover and see it in there. And unless I'm going in for engine work, then I don't really see the need to remove it. My insurance premium increase wasn't too bad either.
For under £400, I think that's fantastic bang for buck. I'll look forward to the summer weather now, I feel I'm overwhelming my poor winter tyres.
If you're on the fence at all about getting your 335i remapped, then do it!
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