Compiling common Gen5 tune changes for Cam, Headers, Thermostat, and Catless

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01-27-2022
Dominatorstang

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Compiling common Gen5 tune changes for Cam, Headers, Thermostat, and Catless

I am trying to compile common tune changes that have become a standard for Gen V with a few common mods. At the same time I am just learning from my research and testing some theories to get my tune dialed in. Here is what I have so far. Please help add and let me know if you see something is a miss.

Big thanks, in no exact order goes out to ghuggins, smokeshow, Higgs Boson, Ben Charles, 5FDP, kevin87turbot, TriPinTaz, lt1z350, cadillactech, cmitchell17 and many others that I am forgetting to mention here. Reading through your posts and/or direct help is how I came up with this list.

Specs
2017 Silverado E92A L86 8L90 3.42gears only tuning ECM (TCM still locked and stock converter)
Cam: BTR Stage 2 - 210/223, .540"/.540", 111 LSA, 14% fuel lobe (stock springs, push rods, rockers, 20deg limiter)
Speed Engineering 1-7/8 long tubes with catless Y pipe (stock muffler)
Hone on stock bore, new Speed pro stock replacement pistons and GM rings
194deg thermostat - was motorad thermostat but started opening very late after 2 months, allowed up to 250degF. Using Murry now but may actually be same company...

Common Issues after a cam install
surging idle - virtual torque and airflow calibration are the two main places to address this.
negative spark at idle - virtual torque model and possibly VVE needing adjustments.
excessive fuel trims at idle - goes back to both the above.

Base Tune
Changes made for cam
Engine>Idle>RPM - added 200 to Base, Rolling, P/N, In Gear (may lower a little when tuning). update: 700-750 recommended idle for this cam.
Engine>Idle>Torque>Limit Offset - bump up around 20% to give bigger window to get it running
Engine>Idle>Torque>External Load - many areas need lowered some, the main idle areas may need cut down to ~25% of original value
Engine>Airflow>General>Cranking Base Airflow - subtract 2
Engine>Airflow>General>Cranking VE Primary - set to 80% for now to get it started easier
Engine>Fuel>Lean/Fuel-Saving - disabled DOD
Fuel System>Fuel Pump>Injection Refill - scaled y axis for edge angle for 14% fuel lobe on cam
Virtual Torque - lowered torque numbers by 40 around idle and smoothed out transition
Engine>Airflow>Variable Camshaft - zero them out for base tune. Tune with set degrees later to dial in VVE and VT tables

Changes made for no cats
Engine>Exhaust>Catalyst - high number in min ECT and low number in max ECT to disable catalyst warmup
Engine>Fuel>General - disabled split pulse crank
Engine>Fuel>Temperature Control - disable Catalyst Protection
DTC's to disable - P0036,37,38,54,56,57,58,60,137,138,13A,13B,13C,13D ,13E,13F,141,14A,14B,157,158,161,420,430,2096,2097 ,2098,2099,2270,2271,2272,2273

Changes made for long tube headers
Engine>Fuel>Oxygen Sensors>Integral Delay>Airflow Mode - bump up 20% for O2 sensors moving downstream a little
Engine>Fuel>Oxygen Sensors>Proportional>Airflow Mode reduce 10%
Engine>Fuel>Oxygen Sensors>Proportional>Limit change to 1.25
Engine>Spark>Knock Sensors - upped cyl number threshold multipliers

Changes made for 194deg thermostat
-Fan systems>Fans>Mechanical thermostat set to 194 (was already set there even though I read stock thermostat is 207...)
-Fan systems>Fans>Control by ECT>Desired ECT - was set for 195 and 222, changed the 222's to 200
-Fan systems>Fans>Control by %>Desired % - bumped up fans speeds to come up sooner.

General Changes to help with tuning
Engine>Fuel>Oxygen Sensors>LTFT Idle Cells Thresholds>Enable VSS=255, Disable VSS=256. This will help with fuel trim issue when entering DFCO.
disable flex fuel if virtual so it will not throw calibration off during tune
disable LTFT's

Tune from log results
I read that cold air intakes will pretty well require MAF calibration
calibrate MAF and VVE - Popular method for MAF+GMVE and suggests Steady state filters https://forum.hptuners.com/showthrea...ation-for-gen4
Spark advance
Virtual Torque - log delivered torque on a MAP graph and on a Airmass graph side by side. Now review log and see what cells correspond. Shift and adjust VT table to match.
Engine>Idle>RPM>Adaptive Idle>Speed Control>Immediate and Predicated - may need some fine tuning to not over correct or under correct
Engine>Idle>Torque>Adaptive Idle>Idle Torque Limit>External load - log zero pedal torque into this table
VVT limiter - command 25deg advance to verify how far it can go (only if you installed correct limiter to prevent over travel!). Now you also know max travel for tune.
VVT effect on virtual torque and VVE - I am not to this step yet, but set a constant valve timing degree and use logs to tune VVE and virtual torque tables at that degree.
Engine>Airflow>Variable Camshaft - fine tune angle table and the WOT angle.

Unsure about these
?Engine Diagnostics>Misfire>Cylinder Mode and SCD Mode - need to adjust for cam, maybe raise all 10% or just idle areas?
?Tune with EVAP unhooked - I have trouble getting a consistent calibration with EVAP hooked up...
?Fuel>General>SOI Base - I see some say to lower to a given number, others matching to cam event, others raising. So not sure...
?Engine>Idle>Torque>Speed Control Reserve - I read cutting this in half will help with transmission clunk when slowing down and then speeding up.
?TCM tune - probably would help to raise shifts and such to match cam but not planned at this time with the cost of unlock and license. Will if needed though.
?watchout for rich decel messing with fuel trim logs - best I could do was try to filter it out in charts and driving.
02-02-2022
HellKnightHicks

Good info. I found some of that stuf out in the school of hard knocks.

Im not sure ive seen an option related to O2 Location.

disabled split pulse crank - What is that and why disable it?
02-02-2022
Dominatorstang

The split pulse from what I read is to help light off the cats on cold start. It may also help smooth the idle out, but not 100% on that. Mostly see it related to emissions.
02-02-2022
TriPinTaZ

Split pulse is only used at startup. Doesn't need to be changed if you disable cat warmup. But you have to use HPTuners 4.10 or below to have access to the cat warmup tables. For whatever reason the 4.11 beta has removed this access.
02-25-2022
Dominatorstang

Made a few minor updates from learnings so far.
02-26-2022
Smash

Great info, will be using.
03-12-2022
Dominatorstang

A few more small updates to the list.
03-12-2022
Pro Street

Good info!
03-12-2022
Dominatorstang

Quote:

Originally Posted by HellKnightHicks

Good info. I found some of that stuf out in the school of hard knocks.

Im not sure ive seen an option related to O2 Location.

disabled split pulse crank - What is that and why disable it?

Quote:

Originally Posted by Smash

Great info, will be using.

Quote:

Originally Posted by Pro Street

Good info!

Thank you!
03-18-2022
BDPhoto519

This is a pretty solid list so far...

One thing I haven't really seen much around here before is "Engine>Fuel>Oxygen Sensors>Proportional>Limit change to 1.25" under the headers section. Does this limit the range the LTFT can make changes, and if so for what benefit?

Thanks!
03-19-2022
Dominatorstang

That is something I got from GHuggins and he mentioned in another thread some time ago. I believe you are correct, and I think it is just to keep it from exaggerating things with corrections. I too noticed many tunes I have seen did not have this change, but I am running it this way on mine.
04-22-2022
Stuffs

great info, please keep it coming
05-03-2022
cmitchell17

One thing I don't think I saw on there is changes to make if your cam has a bigger fuel pump lobe. So you can scale the row axis (y-axis) of ECM 17062 "Fuel Pump Leading Edge Angle" by the percentage amount of your fuel lobe lift increase.
05-03-2022
cmitchell17

Quote:

Originally Posted by TriPinTaZ

Split pulse is only used at startup. Doesn't need to be changed if you disable cat warmup. But you have to use HPTuners 4.10 or below to have access to the cat warmup tables. For whatever reason the 4.11 beta has removed this access.

I wonder if HP removed them because they are feeling more "heat" from the do-gooders at the EPA? Makes you wonder?
05-04-2022
TriPinTaZ

Quote:

Originally Posted by cmitchell17

I wonder if HP removed them because they are feeling more "heat" from the do-gooders at the EPA? Makes you wonder?

Very likely. I opened a ticket on it and they pretended I had no idea what tab I was talking about. Cobb Tuning had to remove support for a bunch of stuff such as Flex Fuel ability and O2 sensor and Catalyst DTC codes. You can no longer edit any of this stuff for Subaru's. In the latest software, you have to run dual maps for 93 pump and E85. Not only that, since they do not allow the flex fuel logic to run, you have to go back to the days of testing your ethanol content and adjusting the E85 map to compensate. Real bummer for the Subaru community. And a real overreach by the Federal Government. The racing community is such a small amount of people compared to the much larger pollution sources. It's just like in FL where they banned the plastic straw, but didn't ban plastic water bottles and plastic bags. Makes zero sense. But don't get me started on the government lol.
05-04-2022
Natedogg284752

Quote:

Originally Posted by cmitchell17

One thing I don't think I saw on there is changes to make if your cam has a bigger fuel pump lobe. So you can scale the row axis (y-axis) of ECM 17062 "Fuel Pump Leading Edge Angle" by the percentage amount of your fuel lobe lift increase.

So if we are running bigger fuel lobes we need to adjust that in the Fuel pump leading edge angle ?
05-04-2022
GHuggins

Quote:

Originally Posted by Natedogg284752

So if we are running bigger fuel lobes we need to adjust that in the Fuel pump leading edge angle ?

There's actually several tables that need to be adjusted for it....
05-04-2022
GHuggins

Quote:

Originally Posted by TriPinTaZ

Very likely. I opened a ticket on it and they pretended I had no idea what tab I was talking about. Cobb Tuning had to remove support for a bunch of stuff such as Flex Fuel ability and O2 sensor and Catalyst DTC codes. You can no longer edit any of this stuff for Subaru's. In the latest software, you have to run dual maps for 93 pump and E85. Not only that, since they do not allow the flex fuel logic to run, you have to go back to the days of testing your ethanol content and adjusting the E85 map to compensate. Real bummer for the Subaru community. And a real overreach by the Federal Government. The racing community is such a small amount of people compared to the much larger pollution sources. It's just like in FL where they banned the plastic straw, but didn't ban plastic water bottles and plastic bags. Makes zero sense. But don't get me started on the government lol.

How the frig is adding flex fuel to a vehicle hurting emissions when government themselves are pushing for more ethanol in the fuel and compatibility in vehicles? Guess it's making older vehicles able to run on newer worthless fuels instead of forcing them to buy something new that's actually the problem... Well guess it's like diesels all over again - go after something that makes sense then screw it up in every way shape and form :/
05-05-2022
TriPinTaZ

Quote:

Originally Posted by GHuggins

How the frig is adding flex fuel to a vehicle hurting emissions when government themselves are pushing for more ethanol in the fuel and compatibility in vehicles? Guess it's making older vehicles able to run on newer worthless fuels instead of forcing them to buy something new that's actually the problem... Well guess it's like diesels all over again - go after something that makes sense then screw it up in every way shape and form :/

I really don't know. It's just like in Florida where some counties banned plastic straws, yet didn't ban plastic bottles and plastic bags, which is a much larger problem for the ocean. Don't get me started on politics and government overreach. I have no idea why Cobb chose to eliminate the flex fuel logic as part of the EPA pressure. I get not being able to edit catalyst DTC's and such, but ethanol burns cleaner than pump 93.

I have a repository of old HPTuners install files just in case they start removing it from HPTuners. You already cannot turn off cat warmup mode in the latest 4.11 beta. Looks like 4.10.x still retains full functionality.
05-05-2022
Ghostnotes

Quote:

Originally Posted by TriPinTaZ

Very likely. I opened a ticket on it and they pretended I had no idea what tab I was talking about. Cobb Tuning had to remove support for a bunch of stuff such as Flex Fuel ability and O2 sensor and Catalyst DTC codes. You can no longer edit any of this stuff for Subaru's. In the latest software, you have to run dual maps for 93 pump and E85. Not only that, since they do not allow the flex fuel logic to run, you have to go back to the days of testing your ethanol content and adjusting the E85 map to compensate. Real bummer for the Subaru community. And a real overreach by the Federal Government. The racing community is such a small amount of people compared to the much larger pollution sources. It's just like in FL where they banned the plastic straw, but didn't ban plastic water bottles and plastic bags. Makes zero sense. But don't get me started on the government lol.

Thank god I have an OLD laptop with an older version.......That will never get updates..

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