[Lancelot]

Hi

I'm new to JB4, and was testing map 5 with WOT, this is a close to stand still to max revs in 2nd gear

attached is the JB4 log I see the boost doesn't reach its target, being about 4 psi below (blue and pink curves), is this to be expected?
Is there a protection for 2nd gear ?

I have the basic out of the box configuration, so no max boost in user adjustments for any gear.

I'll try to do another test in map 1 to compare.

[eluded]

Try a 5th gear pull to redline

[Bee Pee]

Logs in 1st and 2nd aren't much use.

Log from 3rd gear upwards

[Lancelot]

Ok will do
Makes it more difficult as 2nd gear is already 100km/h at redline
Is there a particular reason why? Just curious

[Bee Pee]

Less likelihood of wheelspin in 3rd gear and upwards, sampling for log is easier/more accurate if revs don't rise quite as quick + I think DME has some tapering of boost in 1st and 2nd to save drivetrain

[frackje]

5th gear goes up to 220km/h on the AH3

[Lancelot]

Originally Posted by Bee Pee

Less likelihood of wheelspin in 3rd gear and upwards, sampling for log is easier/more accurate if revs don't rise quite as quick + I think DME has some tapering of boost in 1st and 2nd to save drivetrain

Makes sense;
I did have a tiny bit of wheel spin in 2nd gear indeed, not much though, and the DME witholding boost makes sense as well, explains why DME boost and DME target also don't align.

I'll do another run in 3rd gear.

[Lancelot]

Just one remark, this test run highlights even more the need for chassis reinforcement, i feel the car is in dire need of LSD to distribute torque to the wheels, and the underbody reinforcement plate, anti roll bars and front struts bar i have scheduled will definitely help.

I think too many people tune their engine to achieve numbers and neglect the chassis :-/

[Bee Pee]

Jb4 users oracle.....

http://f30.bimmerpost.com/forums/att...8&d=1433827618

[Lancelot]

Thank you, I had indeed read this before asking and was indeed curious why the actual and target boost didn't align, as they mostly do in all the samples attached.