Jb4 question




Feels faster but don’t have great times yet.
took it off to bring it into the dealer and the car feels better/tighter back stock.
anyone else experience this?
the car feels looser / erratic with the jb4, maybe that’s why my 0-60 aren’t improving?




without 12.27
with 11.10
which is why things are confusing me
i was hoping to be 3.6-3.7 0-60
and 11.5 1/4
i think others are doing these times.
I’ll keep working and logging
The biggest thing that stands out to me is that the JB4 seems to actually hurt low end performance. My stock 60ft times were a bit better than with the JB4, but my trap speed was higher by a couple MPH.
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Last edited by Griley; Apr 24, 2022 at 10:14 AM.




it was CPO, and has been in the dealer many times I’m sure it had some coding done when I got my center Speedo screen replaced.
Last edited by MaverickC43; Apr 26, 2022 at 09:19 AM. Reason: Spelling




How would one find out what tune has been applied to their car? Is there a digital signature that a Xentry system could read that would identify the company?
Last edited by GermanCarShow; Apr 26, 2022 at 11:13 AM.




and even more concerning is that the fai didn’t improve performance. Most people said you’d see gains with an intake & tune



