ChrisR6s

Ok so there seems to be ALOT of confusion out there about the learn down feature (not technically an accurate term) in our LNF cobalts and so I decided to reach out to someone I know could explain it correctly. I see people say its still active with GMS1 and then its turned off also. I see people say there is no point in modding a stock tune LNF BECAUSE of the learn down feature so i just really wanted to clear this up because i was also confused as to what was true or not. here was my question to ZZP........ sent today 4/18/2019 and replied today by ZZP.

ME-Hello can you clear up a question for me that the forums cant seem to agree on. With the tune you guys did to my car last week (08 LNF) is the learn down feature still active? And when I order my 3 inch catted DP (400 cell cat) do i need to send in my ECU for a retune?

ZZP Reply- Let me start by saying that there is no such thing as a learn down feature. The LNF ECM is designed to achieve a specific air load target based on the calibration. People started calling this “learn down” because if you add a mod to your engine that allows it to flow better, the ECM will simply dial back the boost slightly in order to maintain the same power output. However, if you drive to a higher elevation or on a hot day, the ECM will still attempt to achieve the same power level. Of course, no one calls it a learn up feature, even though it can do that just the same. It would be more accurate to say that the ECM has a load target feature. Now, having said that, this is not a factor with our tuned LNF ECM’s. While you may see small adjustments in midrange torque, your peak power will not be limited by an air load target setting. The reason for this is simple. We actually set the ECM file up to achieve about 10-15% more than the engine can achieve with the factory turbo in place. At approximately 5600 rpm and higher, your turbo will be running at 100%. Even if you add every airflow mod available, such as stage 2 cams and a ported head, air intake, Etc. You will still see 100% duty cycle on your wastegate solenoid by the time you reach 5800 rpm.

Becky M. ZZPerformance

I really hope this helps any confusion. and i only put this out there (not to be rude or anything) to make sure people have the correct info on our AMAZING cars!!

CudaJoe

iTrader: (1)

Their were people confused by this>? I understood what learned down meant the day it became a coined term. Its not a feature, its not something you can physically turn on and off. That email does explain what it means perfectly except for the "learn up" comment, that sounds silly. Example if you restricted airflow at the intake by blocking 3/4 of the filter, I do not think the car is going to max out the boost to ensure it meets the air load target, there's a limit to that.

You can see the "learn down" happening all year long on the stock tune. Winter = lower boost, summer = higher boost.

Slowbalt2000

iTrader: (1)

Yes there is a limit but what you just described is still "learning up"

steelmesh

I take it the work around for this at all levels is to increase all the torque tables?

Kolt

From what I understood from gm is the factory tune wants to meet a maximum calculated output of torque based on throttle request. Bolt on mods will not cause hardly any MAXimum increase but will help increase the midrange "some". Also like zzp stated. At high altitudes or hot days, those mods will give enough performance boost to let the ecm still produce close to or at the maximum torque output. For example comparing a more efficient oversize intercooler to stock intercooler, on a hot day the stock one will cause the ecm to pull timing and boost due to higher iat at the manifold than that of a better aftermarket intercooler. thus you lose some power.

ECaulk

iTrader: (6)

Yeah, that isnt anything new. The ecu is torque based and adjusts to meet the various tables that demand a certain air flow to produce a certain torque.

Over on the hptuners forums there is a pretty much complete break down of the ecu explaining this and anyone trying to tune an LNF is not coming to this site to learn how

ChrisR6s

I thought it was a pretty good way for Becky to say it so i understood, Makes more sense to me now.