[BMSE92_Harry]

I was on the forum learning more about the JB4 and the mobile app. There was a discussion in there where one claim that JB4 is only a boost controller and can cause transmission to slip because JB4 doesn't allow TCU to see true load, and send fake signals to DME->TCU.. which the user suggested that it was because of the piggyback tune is the culprit.
I personally have a JB4 G5 and love it so far, I know people that are pushing 400+ HP with JB4 with FBO running E85. I just want to know what the community think how true this is. So far, I've only come across one person dealing with tranmission slip due to tune.

By no mean I am asking which tune is better, I know the advantage and disadvantage of each tune. There are plenty of post comparing them already.

http://www.e90post.com/forums/showth...le+app&page=12

[csu87]

dont worry about what that one guy who clearly has a bone to pick says.

Tons of guys are running high power setups with the JB4

[tc535i]

this is an issue with DCT transmissions

not an automatic problem

anybody with a slipping auto is due to the extra power, not the style of tune

[mike@x-ph.com]

Tens of thousands of Jb4 users have no transmission slippage.
It is proven that unless you go over 500 wtq, your transmission is fine.
Once you go over that, you will start noticing slippage on any tune.

[brewnami]

That's quite a claim for the most popular tune for the N54 platform. Also, if you buy a car with a proper gear box, you won't have to worry about slipping ; )