2019 C43 JB4 performance
power delivery is completely different in the facelift - blow off noise - and many sources indicate such. Dyno charts also show the power delivery being different.



https://www.n54tech.com/forums/showp...&postcount=769
https://burgertuning.com/products/op...control-module

The Best of Mercedes & AMG

https://www.n54tech.com/forums/showp...&postcount=769
Uhhhh, the 2019s are NOT running less boost from the factory....they're running more.
https://mbworld.org/forums/c450-c43-...g-results.html
Last edited by alexasa; Jun 17, 2019 at 03:59 PM.
Electronic wastegates (like what's on these cars) tend to have a limited range of indirect adjustment (like across the canbus or through changes to other sensor inputs), before the chances of seeing oscillations and spikes of actual boost above target boost increase. That range is usually ~10-15% above stock boost. The higher stock boost levels on the 2019s probably magnify this limitation, because 10-15% of 16 psi is larger than with 12 psi. The boost control module add-on is giving them direct control over pid and wgdc and should keep actual boost much more in line with the target, and those big throttle closures should largely be a non-issue after that. I don't know if firmware will actually resolve it, I don't know how much I/O capacity is available on the JB4 board used with this car. However, even a firmware fix may not address the overboosting, as there are still limitations on the amount of finite control you get using indirect methods to control pid and pwm. The boost control module may be the only way on the 2019.
Electronic wastegates (like what's on these cars) tend to have a limited range of indirect adjustment (like across the canbus or through changes to other sensor inputs), before the chances of seeing oscillations and spikes of actual boost above target boost increase. That range is usually ~10-15% above stock boost. The higher stock boost levels on the 2019s probably magnify this limitation, because 10-15% of 16 psi is larger than with 12 psi. The boost control module add-on is giving them direct control over pid and wgdc and should keep actual boost much more in line with the target, and those big throttle closures should largely be a non-issue after that. I don't know if firmware will actually resolve it, I don't know how much I/O capacity is available on the JB4 board used with this car. However, even a firmware fix may not address the overboosting, as there are still limitations on the amount of finite control you get using indirect methods to control pid and pwm. The boost control module may be the only way on the 2019.
-Payam
Electronic wastegates (like what's on these cars) tend to have a limited range of indirect adjustment (like across the canbus or through changes to other sensor inputs), before the chances of seeing oscillations and spikes of actual boost above target boost increase. That range is usually ~10-15% above stock boost. The higher stock boost levels on the 2019s probably magnify this limitation, because 10-15% of 16 psi is larger than with 12 psi. The boost control module add-on is giving them direct control over pid and wgdc and should keep actual boost much more in line with the target, and those big throttle closures should largely be a non-issue after that. I don't know if firmware will actually resolve it, I don't know how much I/O capacity is available on the JB4 board used with this car. However, even a firmware fix may not address the overboosting, as there are still limitations on the amount of finite control you get using indirect methods to control pid and pwm. The boost control module may be the only way on the 2019.
Electronic wastegates (like what's on these cars) tend to have a limited range of indirect adjustment (like across the canbus or through changes to other sensor inputs), before the chances of seeing oscillations and spikes of actual boost above target boost increase. That range is usually ~10-15% above stock boost. The higher stock boost levels on the 2019s probably magnify this limitation, because 10-15% of 16 psi is larger than with 12 psi. The boost control module add-on is giving them direct control over pid and wgdc and should keep actual boost much more in line with the target, and those big throttle closures should largely be a non-issue after that. I don't know if firmware will actually resolve it, I don't know how much I/O capacity is available on the JB4 board used with this car. However, even a firmware fix may not address the overboosting, as there are still limitations on the amount of finite control you get using indirect methods to control pid and pwm. The boost control module may be the only way on the 2019.
In this specific example (CSV on the first page somewhere) throttle is closing during engine deceleration post shift, but the throttle is oversized and would have to close dramatically before it would effect manifold boost (e.g. actual performance). No such change to manifold boost is seen in this log. So this is normal behavior here. If you hacked in to the flash map and bypassed the throttle follower forcing zero throttle closure you'd get ZERO performance gain. With this specific example.
If you have other example I'm happy to look at them. Devil is always in the details.
Last edited by BMS; Jun 18, 2019 at 11:00 PM.






