It would be great if this thread contained facts, and is not the usual ECU tune vs piggyback fanboys fuckery
I've been taking to OP about this over last days. To help people understand this problem:
This is an issue with wastegate scaling on cars with electronic wastegates. WGDC is commanded by the ecu on its scaled map profile based on what duty cycle it thinks is going to need for a target torque/boost target.
The OEM mapping for
EWG DC is profiled based on spool characteristics of the OEM DP and full Exhaust. Two things are happening here.
1. The cold air is denser so it makes more boost for a given wgdc. For example Air that is in the single digits F is 10% denser than even 32 degree temps. Meaning 10% more boost. The OEM iat modifier table usually accounts for this by dropping target boost for a given temp/airmass.
2. The full catless setup is making more boost, way faster for a given DC.
This is not the normal overboost suppression issue which piggy backs normally tackle easily by spoofing reported map signals back to ecu.
This is factory ecu commanding more DC than is actually required given the new spooling profile, thus overshooting it's " requested" torque/boost.
As far as I am aware, no current tuning solution either piggy back or flash tune can directly address the the root of the issue, which could only be addressed by either intercepting and directly controlling the
ewg, or having access to the scaling tables for
ewg control maps in the ecu.
What Jesse is asking in this thread is comments and feedback from
1. People who are catless
2. People who are in cold climates with DP
3. People who have both and are logging behaviors
I've had slightly similar issues, on occasion but only in initial spool, it levels out to normal levels of 19ish psi on map 3 jb4 in weather around 30-40 f. Given the snow and I live in the city, I've not had occasion to get hard runs in to see if I'm having the same level of issues that op is having. I'm going to try to get some runs in this -15 c weather and see what happens. Attached is screen cap of what we are discussing