JB4 for Audi S4 B9

Johnny potts

New Member
Morning Guys,

Does anyone have any experience of running a JB4 REV 2 box on their S4 B9 or even older/other models.

really debating getting one. I don’t want a remap due to warranty etc etc. But a plug and play box with mobile controls seems the best fit for me.

Open for recommendations, horror stories or whatever to help my decision.



Registered User
Try Audizine - I have seen posts from a fair few B9 owners with a JB4.


Registered User
I love them, I'm not running one in the S4 as I'm out of warranty so went with Unicorn!

However I ran one for 2 years on my Leon Cupra, stock it dynoed at 303, with the jb4 and my own Map6 I made 375hp!

Id you buy new you'll get George form BMS support if you wanted to create a custom, howe er from what I've seen on the S4 the preset maps are more than enough!


Registered User
I run a dtuk box on my s4 and love it, made a huge difference, obviously not as much as a map but the difference is night and day


Registered User
I ran a DTUK until I could get a map - as other say, night and day difference. I still have it if you're interested?


Registered User
I had the JB4 and still do. I had the rev1 support is very good and the additional bump in power makes the car drive as it should. On map5 I was dyno at 441.6bhp and 517ft lbs of torque.

much better than the DTUK box as people were having lots of problems with them.

I also ran some good 1/4 miles times got as low as a 11.69 and 0-60 of 3.45 I would say go for it if you want to keep warranty.