[ritzzzzzwik]

OMG dont dot it! My friend installed JB4 and turned the ignition on..BOOM! Shrapnel everywhere, I almost went blind looking at the explosion.
My friend died, but now he is better

Ok, so none of that really happened

JB4 is absolutely fine! I had it on my car for ages, and so did/does everyone else. I went custom flash tuning later, but JB4 is top notch.

Be prepared to replace plugs and coild sooner (25-30K miles). Stay on top of general maintenance, and you'll be absolutely fine! JB4 doesnt even push the turbos to the max. There are people running much higher boost on stokers, and they are absolutely fine.

Good luck and enjoy the power!

[talhagursoy]

I don't really recommend JB4 for Z4 DCT. I used it for 6-7 months and doesn't matter whatever you do, you always have problem with your DCT. I believe one guy in e89 forum claimed that JB4 killed his DCT and replacement cost him over $10k. So why don't you go with MHD tune. There are a lot of bias in Istanbul about tunes, piggy backs and any other engine performance stuffs. Another one is "Yazilim", which is the biggest bullshit I have ever heard.

[jskin1510]

Regardless of what tune you would go with i would replace the spark plugs first. Normally, i would say coil packs also... but with 19k, yours might be fine for a little while. probably also depends on if you are running a mild map like map 1 (you would still notice a big difference in power vs not tuned) or more aggressive (like map 5). I'm sure if you ran map 5 the coils would start going a little sooner than if you were running map 1 all that time.

If you don't change coils, my guess would be you get a misfire probably 1 at time, replace 1 shortly after, probably get different one... so might be best to just replace all 6 at once. I say this because i added my jb4 at 91k or so and over the past year since i added it, 3 of the coils (one at a time every few months), started to give me misfires and i'm only on map 1. Soon as i replaced the bad one, can run hard on map 1 fine again. What i thought was interesting with this is i could run the car hard with tune off (map 4) and no misfires but just switching to map 4 and stepping on it was enough to wear the bad (or going bad) coil couldn't handle it.