JB4 info and discussion thread

Shawn8V

Registered User
Hi guys, looking for some advice regarding the JB4 before I bite the bullet;

1. How do you switch between maps 1-8 (or however many there are)? Laptop every time if I don't purchase the Bluetooth hardware & software?

2. I noticed that you have to puncture a rubber bung in the bulkhead for an OBD2 connection - my understanding was that there were only 3 connectors to disturb (camshaft, boost & MAF sensors) - what does the OBD2 connection do?

3. Where does the JB4 unit receive its power supply from? Is it picked up from one of the wires in the loom or do you have to tap into a 12V source?

Cheers,

Greg.

PS cracking thread @OliS3

1) you can use a laptop with the free software. You’d need to buy a cable tho. There’s only 3/4 maps which are useful for a normal person.

Map1 - lower boost map (wouldn’t ever bother with this unless you put in 95 Ron)
Map2 - higher boost map (99 Ron needed)
Map0/4 - bypass map - bypass with logging.
Map6 - custom map boost per rpm.

If you want a set and forget set up then set it to map 2 using a cable and laptop and forgot about it. If you want a map 6 and tune yourself then the Bluetooth and app are better imo.

2) Rev 2 units (latest models) have 3 connectors to the engine. 2 at the top and 1 under the bottom which can be pain to get too. An AFR tap and an obd connection. These allow for more boost and a smoother ride. If you don’t use these then the JB4 will stay on a stock map similar to map1.
Obd connection isn’t hard at all to get into the cabin.

3) Power is picked up from the engine connectors. No 12v direct feed line needed, unless you’ve got the Bluetooth module then you can run it to the battery with a small 1amp fuse which is what I have done. (I have the older rev1 unit, so its smaller and fits in the battery cover with the Bluetooth dongle).

With a proper set up map 6 and bolt on mods you can get about ~400bhp.
 

Shawn8V

Registered User
I know it's a pretty specific question but have anyone done the following comparison? If so, what was your impression?

Dynamic mode, ESC Off (or Sport), acceleration from stand still:
1. Boost limited in 1st (0.1 psi) and launch control
2. No boost limit in 1st and just flooring it without launch control

With tc in sports mode/fully off I do find it gets off the line a lot of quicker without launch.

No boost limit in 1st and flooring it has no issues

Can’t comment on launch control and boost limit in 1st gear. I just like to feather the throttle at about 3k instead of the 4.5k and then dump the brake and I find it goes off with no problem. With no boost and full 4.5k the gearbox gets confused as it’s not seeing the true torque value and doesn’t make a nice noise aswell.
 

GregS3

Member
It's my birthday
1) you can use a laptop with the free software. You’d need to buy a cable tho. There’s only 3/4 maps which are useful for a normal person.

Map1 - lower boost map (wouldn’t ever bother with this unless you put in 95 Ron)
Map2 - higher boost map (99 Ron needed)
Map0/4 - bypass map - bypass with logging.
Map6 - custom map boost per rpm.

If you want a set and forget set up then set it to map 2 using a cable and laptop and forgot about it. If you want a map 6 and tune yourself then the Bluetooth and app are better imo.

2) Rev 2 units (latest models) have 3 connectors to the engine. 2 at the top and 1 under the bottom which can be pain to get too. An AFR tap and an obd connection. These allow for more boost and a smoother ride. If you don’t use these then the JB4 will stay on a stock map similar to map1.
Obd connection isn’t hard at all to get into the cabin.

3) Power is picked up from the engine connectors. No 12v direct feed line needed, unless you’ve got the Bluetooth module then you can run it to the battery with a small 1amp fuse which is what I have done. (I have the older rev1 unit, so its smaller and fits in the battery cover with the Bluetooth dongle).

With a proper set up map 6 and bolt on mods you can get about ~400bhp.
Thanks for the informative response! @Shawn8V

Can you tell me more about the AFR tap? Is that the red wire that is spliced into, at the back of the engine bay?
 

Shawn8V

Registered User
Thanks for the informative response! @Shawn8V

Can you tell me more about the AFR tap? Is that the red wire that is spliced into, at the back of the engine bay?

Yes it’s the red wire on the grey plug on the back of the engine bay. I’m in the process of making some wire harness’s for this instead of tapping into the wires. Work in progress atm.
 

GregS3

Member
It's my birthday
Yes it’s the red wire on the grey plug on the back of the engine bay. I’m in the process of making some wire harness’s for this instead of tapping into the wires. Work in progress atm.
Am I right in saying that the OBD2 cable is longer than normal (for RHD cars) to allow you to route it through the passenger side, avoiding the turbo & downpipe (hot zone)?
 

Shawn8V

Registered User
Am I right in saying that the OBD2 cable is longer than normal (for RHD cars) to allow you to route it through the passenger side, avoiding the turbo & downpipe (hot zone)?

I first routed it along the firewall going past the downpipe and turbo but the cable melted and stopped working within a few weeks, Got a replacement cable and covered it with a glass fibre heat resistant cable against the same route. No problems after 10k miles.

You can run it into the cabin near the battery but that’s too much hassle for me. But yes the cable is longer for RHD vehicle I believe.
 

Lehn

Registered User
With tc in sports mode/fully off I do find it gets off the line a lot of quicker without launch.

No boost limit in 1st and flooring it has no issues

Can’t comment on launch control and boost limit in 1st gear. I just like to feather the throttle at about 3k instead of the 4.5k and then dump the brake and I find it goes off with no problem. With no boost and full 4.5k the gearbox gets confused as it’s not seeing the true torque value and doesn’t make a nice noise aswell.

Sounds great, then I don't need to worry about LC. When you feather the throttle does the car go into LC mode? (If you know what I mean).

Could you share your map 6 settings and maybe upload the video again of you and the RS3 facelift?
 

Shawn8V

Registered User
Sounds great, then I don't need to worry about LC. When you feather the throttle does the car go into LC mode? (If you know what I mean).

Could you share your map 6 settings and maybe upload the video again of you and the RS3 facelift?

Yes the car does go into launch control mode, but sometimes it but changes changes earlier at 6.5k and you hear the upshift pops and sometimes it goes almost to 7k and you don’t hear any. Both don’t really make it any slower imo.

I can share my settings but unless you got a high flow downpipe, intake and intake pipe etc they’d be no use to you.

I’ll pm you a link to that video.
 

Lehn

Registered User
Yes the car does go into launch control mode, but sometimes it but changes changes earlier at 6.5k and you hear the upshift pops and sometimes it goes almost to 7k and you don’t hear any. Both don’t really make it any slower imo.

I can share my settings but unless you got a high flow downpipe, intake and intake pipe etc they’d be no use to you.

I’ll pm you a link to that video.

Just what I want to hear, thanks!

I don't have that and don't think I will get it. I'm just curious to know how much boost you add relative to each other and not the amount of boost you add. It might also be helpful to others with the same bolt ons as you.
 

Lehn

Registered User
With tc in sports mode/fully off I do find it gets off the line a lot of quicker without launch.

No boost limit in 1st and flooring it has no issues

Can’t comment on launch control and boost limit in 1st gear. I just like to feather the throttle at about 3k instead of the 4.5k and then dump the brake and I find it goes off with no problem. With no boost and full 4.5k the gearbox gets confused as it’s not seeing the true torque value and doesn’t make a nice noise aswell.

Tried to make a launch today but with releasing the brake the second the rpm would hit 3k. The cluth engage was very harsh and I kind of felt the car make a jump forward before continuing. There was no smoothness in the cluth engage as in the normal launch control.

I have made a lot of normal launches so I know what it's all about but maybe I'm doing something wrong? Got it on my dash cam so if it's obvious on the video I will try to uploade it.
 

Shawn8V

Registered User
Tried to make a launch today but with releasing the brake the second the rpm would hit 3k. The cluth engage was very harsh and I kind of felt the car make a jump forward before continuing. There was no smoothness in the cluth engage as in the normal launch control.

I have made a lot of normal launches so I know what it's all about but maybe I'm doing something wrong? Got it on my dash cam so if it's obvious on the video I will try to uploade it.


I’ll pm you a link to a video showing how I do it, maybe it won’t work for you since you have the new 7 speed dsg and have the 6 speed dsg.
 

FBF01

Registered User
Is there going to be a JB4 for the RS3 fl that anybody knows about?
 
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Lehn

Registered User
Just got a Jb4 for my S3 what is the best settings for a manual one.

Did you figure something out? Otherwise George from BMS suggests to use the below settings for manual:

1500 0
2000 2
2500 3
3000 3.5
3500 4
4000 4.6
4500 5
5000 5
5500 5.4
6000 5.4
6500 5.4
7000 5.0
 

boydyski

Registered User
JB4 AFR Looms for sale.

£35 posted to the uk.

Hi, could you (or someone) tell me the purpose of these please? I've just bought the JB4 upgrade kit for my JB1 (rev 1); are these to use instead of the posi-tap into the red wire?

Thanks.
 

Lehn

Registered User
Hi, could you (or someone) tell me the purpose of these please? I've just bought the JB4 upgrade kit for my JB1 (rev 1); are these to use instead of the posi-tap into the red wire?

Thanks.

Short answer: yes. It's easier to reverse to stock when going in for service etc.
 

boydyski

Registered User
Short answer: yes. It's easier to reverse to stock when going in for service etc.

Thank you, sounds like a good option for me.

I know the blue JB4 wire gets tapped into the red wire at one end and then into the JB4 harness at the other, how does this bit of kit differ exactly? Does anyone have any images of it installed? What does the little clip that spurs off with the yellow on it connect to?
 

boydyski

Registered User
Fitted my JB4 upgrade kit yesterday and didn’t get any warning lights flash up when I started the car...is this normal as the guide says some should show?

It feels smoother but can’t say I feel a huge increase in power over the JB1.
 

boydyski

Registered User
Fitted my JB4 upgrade kit yesterday and didn’t get any warning lights flash up when I started the car...is this normal as the guide says some should show?

It feels smoother but can’t say I feel a huge increase in power over the JB1.

So it turns out the JB4 was set to Map 1...a quick switch to 2 and a few laps round the block have assured me that yes, it is indeed working!
 

Lehn

Registered User
A question just came to my mind; is it possible to run an additive custom map 6 but still limit boost in 1st with an absolute boost value, like 18.5psi?
 

morgan dent

Registered User
long time member, but first post... My 8v FL was dynod at 335 stock, do you think id see improvments with a JB tuning box?
 

Salik Sajid

Registered User
Yes obviously with different maps u will see differences of power, my 8v 1.8T stock 181whp, map 1 on 91 octane made 221whp with downpipe and drop-in filter.

Sent from my HTC 10 using Tapatalk
 

boydyski

Registered User
long time member, but first post... My 8v FL was dynod at 335 stock, do you think id see improvments with a JB tuning box?
Definitely! I was running the JB1 for a bit then upgraded the board to a JB4. At each point the difference was really noticeable, especially with the JB4 - the car is far more urgent to get going. It’s still quite pricey, but less than a full ECU map. Plus if you add any performance hardware you can tweak the maps on the JB unit as you go.

I have a PFL with panel filter, turbo muffler delete, large bore turbo inlet pipe, centre res
delete and pedal box. I’d be very surprised if I’m under 360bhp. The JB4 is advertised to give 45bhp without any bolt-ons.

Hope this helps!
 

morgan dent

Registered User
Has anyone had any issues which have resulted in a warrenty claim from one too? just wondering if audi could plug diagnostics in and see that boost has been much higher than normal
 

WozaS3

Registered User
Well, after months of debating and procrastinating.. I bit the bullet and bought a JB4, spent a further two weeks procrastinating again and finally decided to fit it today.. pretty easy to do, charge pipe sensor was a bitch though

Holly.****.

Went balls deep straight to map 2 - car feels like it’s on steroids!! HUGE difference!

Definitely going to get in to trouble
 

Sohrob

Registered User
I no longer have an s3 but I have just had A JB4 fitted to my 2019 Leon Cupra 290 (PPF) and the car made 350 bhp on Map 2 at RS tuning Leeds (Dyno dynamics rolling road).

The only engine mods are Forge intake pipe which also replaces the turbo elbow, panel filter and snowgrate removed/air feed opened up.

The car has only done 1500 miles but has only ever been run on V power and had the oil changed to Miller Competition.

I’m going back in a few weeks to setup map 6 on the dyno.
 

Shawn8V

Registered User
I wouldn’t worry about the dyno figures as they tend to vary between dynos, get yourself a draggy or vbox and see the performance differences between the maps using that.
 

Sohrob

Registered User
I have a dragy, waiting for the weather to improve.

Whilst I’m not overly bothered about figures it’s nice to know, especially when stage 1 cars are putting out less power on the same dyno.
 

Damo S

Registered User
How do you guys find the 2nd gear acceleration with the JB4? Is it much quicker? In stock form I always find it slightly underwhelming although 3rd gear then seems to pull pretty much as strong as 2nd did. Assuming my car behaves itself from now and until July I may look at purchasing and installing one.
 

OliS3

Registered User
How do you guys find the 2nd gear acceleration with the JB4? Is it much quicker? In stock form I always find it slightly underwhelming although 3rd gear then seems to pull pretty much as strong as 2nd did. Assuming my car behaves itself from now and until July I may look at purchasing and installing one.
In stock form the car limits boost in the first 2 maybe 3 gears. With the jb4 you can get around this to some degree and 2nd gear feels a lot better.

Sent from my SM-G960F using Tapatalk
 
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