Custom MHD map lazy launch control

hardneoark

New Member
Jan 4, 2022
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0
0
Hello spoolstreet community, requesting some help from the custom tuners here!

I and one friend recently installed a Vargas GC turbocharger on two M340i G20 xdrive B58TU.

I did a custom MHD map for both cars, mostly increasing the "boost set limit", "boost multiplier" and the "torque to load x axis breakpoints" to increase boost, We're currently getting great results with the raw speed of the cars hitting very good numbers with dragy measurements... except for the launch control. LC is working fine but it takes too long to build all the boost to do a proper launch. We've been tweaking custom launch control settings on XHP with no success to make the launch control build boost faster. This is happening to both cars.

I guess this is a symptom caused by the turbo being bigger, the same issue happens if We use the stock map for both cars.

We tried the JB4 backend flash for pure turbos (since both cars have Jb4 installed for ease of use for boost control) but we had the same results.

Does anyone know any table or tables on Tuner Pro I can adjust to make the launch control build boost faster?

Thanks in advance!
 

wheela

Captain
Jun 4, 2021
1,237
708
0
Twin Cities, MN
Ride
2015 e84 X1 35i Msport
Is the issue that it takes a long time to build boost while getting ready to launch, or that it doesn't build up much boost before you let off the brake and the car actually starts moving (no matter how long you hold the launch control)?
 

hardneoark

New Member
Jan 4, 2022
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It takes a long time to build boost. Once you let it charge, it launches very hard but it's just that it takes more time, everyone tells me is normal since the turbo is bigger then it has slower spool, which makes sense for sure, just wondering if there is a way to improve the spooling time on the LC.
 

Kynetic335boost

New Member
Sep 10, 2020
4
0
0
Pittsburgh PA
Ride
07 335i E90 6 spd
Well are you using the Custom Antilag Compressor Base and P- Factor tasbles?> also have you adjusted the Antilag timing table for a bigger turbo? Are you logging your Antilag timing to see if your hitting the timing you need and are supposed too. Timing P factor as well as I factor have you adjusted any of those or are you just running OTS numbers
 

hardneoark

New Member
Jan 4, 2022
6
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0
Well are you using the Custom Antilag Compressor Base and P- Factor tasbles?> also have you adjusted the Antilag timing table for a bigger turbo? Are you logging your Antilag timing to see if your hitting the timing you need and are supposed too. Timing P factor as well as I factor have you adjusted any of those or are you just running OTS numbers
Thank you for taking the time to reply.
Currently, the ECU doesn't have installed MHD custom code, as it was sent to femto when this wasn't available, therefore I don't have access to the antilag tables. As for the P and I factor tables, the map is running OTS values, can you give us some advice on how to change these tables to improve the LC charge time? These are the boost tables at my disposal:

boost tables.png
 

mikesrex

Specialist
Mar 11, 2018
72
31
0
Ride
2015 X5 and 2008 535i
Do you have a log of what’s going on? I think the transmission might limit tq if you are brake boosting at a standstill for too long. Those is where a custom transmission tune could help, or the boost getting there faster might help. I have this same issue on my G30 when using a tune with my custom wgdc tables not yet dialed in. Going to play with those more and also ask my transmission tune guy what he thinks. The car runs perfect on launch when I’m using conventional body control, but id like to eliminate the slight overboost and throttle closure on WOT up shift. I posted logs of a good and bad launch in my recent thread
 

Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
979
907
0
New York
www.twistedtuning.com
Ride
N54 and N55 Cars
with a vargas GC, you should be able to build a decent amount of boost. hell we build 13-20psi for launch on an EFR9280. and that was before antilag was available .


what RPM are you stalling at?
 

hardneoark

New Member
Jan 4, 2022
6
0
0
with a vargas GC, you should be able to build a decent amount of boost. hell we build 13-20psi for launch on an EFR9280. and that was before antilag was available .


what RPM are you stalling at?
Well, it builds a decent amount of boost using launch control from idle at 1200rpm till 2900rpm approx before releasing the brake pedal, but it takes about 3 seconds to accomplish this, We'd like to shorten that time if possible.