[cellsafemode]

I have no experience in tuning. But from what i've seen from others who have mentioned things about the 2016 is that the ECU is tuned by modifying cells for target torque values.

If that's true, then wouldn't any bolt-on changes result in (at best) a temporary change in hp/torque as the ECU learns how to correct engine performance to return to it's target torque value?

In such a setup, the only way you'd improve your numbers long term is if something was keeping the car from hitting it's targeted torque values prior to the mod.

any tuners with experience on the 16's know if that's basically how things are working?

[oldman]

I'm just learning the HP tuner, I can say my Long Term Trim A/F modifiers are very different than say the stock box Trims. I don't know what the negative numbers mean and in the next few days I'll put out some cut and paste. What I did notice is that the trims for the CAI CAI are inverse from that of the stock box. My other mods are: cat delete, MSD intake. Also I have not seen any knock on any run so far! Either the advance is very conservative or the DI flame front is very good, or both. Dunno. I'm on A/F and MAF tables. Looking forward to a lively discussion and by this time next year, I'm sure there will be shared tunes for:
stock: 91 and 93
CAI CAI: GM's version, and our own userbase with 91 and 93
CAI CAI, MSD INtake: 91 and 93
CAI CAI, MSD Intake cat delete and probably crush pipe back: 91 and 93
CAI CAI, MSD INtake, full header with cat, stock exhaust: 91 and 93
CAI CAI, MSD Intake, full header with cat, complete exhaust 3": 91 and 93

[cellsafemode]

did your cai retain the same diameter tube as stock with airflow regulators to reduce the turbulance of the air moving across the sensor like in the stock box?

if any of those are no, then I would assume the car is not getting an accurate reading of how much air is coming into the engine assuming you haven't made the necessary corrections. Might have something to do with your values. maybe-maybe not.

I'll be keeping my eye out for the 2016 V6 support from hp tuner. So far it doesn't look like it exists yet.

[Tuned Camaro]

Originally Posted by cellsafemode

I have no experience in tuning. But from what i've seen from others who have mentioned things about the 2016 is that the ECU is tuned by modifying cells for target torque values.

If that's true, then wouldn't any bolt-on changes result in (at best) a temporary change in hp/torque as the ECU learns how to correct engine performance to return to it's target torque value?

In such a setup, the only way you'd improve your numbers long term is if something was keeping the car from hitting it's targeted torque values prior to the mod.

any tuners with experience on the 16's know if that's basically how things are working?

The ECM adapts to changing conditions via the short and long term fuel trims. There are two calibrations that when deviated from will cause a change in the trims... the VE table (now calculated in real time and not an actual table) and the MAF transfer function (or MAF table). If you make a modification that causes either calibration to no longer reflect actual then you will see a change in the trims. Now the trims can only adapt to a certain extent before you will see a CEL. For minor mods you will remain within the range the trims can adapt for. Now even if you stay in the range it does not mean things are optimal at WOT. If your trims are significantly negative this indicates that at part throttle too much fuel is being delivered and the ECM is pulling it back. For part throttle this is perfectly fine. But what you won't know until you put a wideband sensor on the car is if your WOT fueling is too lean or not. Now if your trims are significantly positive during part throttle this means that the ECM is adding additional fuel beyond what the calibration calls for to keep things at stoich. Fine for part throttle... but at WOT you won't know if your AFR is fine or if you will now be rich and losing power.

In an ideal situation every modification that affects reported airflow or changes the VE of the engine will see a tune to recalibrate things correctly. To do this is time consuming and most shops will not do more than a MAF tune. But taking the time to recalibrate the MAF and the VE table IS the "correct" way to do things. But it will take over a day and be very expensive if not doing it yourself.

The MSD intake by itself will be accounted for pretty well by the factory calibration as it is post MAF. Even adding the cat delete pipes is going to do fine. BUT... putting a cold air intake on with those mods will definitely warrant at least throwing a wideband on the car and checking to see where things are at at WOT. The cold air intakes absolutely will throw off your MAF transfer function unless a lot of work was done to ensure that the stock and cold air MAF outputs match pretty damn closely (unlikely).

The driver demand torque tables, at least within the context of what we have access to in HP Tuners or EFI Live, are really only used by the ECM as essentially torque limiters. At pedal % and MPH I want the car to produce X ft lbs of axle torque. They really don't change the fueling calibrations.

The factory calibration (i.e. stock) has to accommodate every single possible scenario one might face. Low octane fuel, high elevation, low elevation, cold, hot, etc... it is close but is not perfect in delivering maximum performance. Tuning is needed to maximize it as well as adapt optimally to your modifications.

I've seen a 2014 ProCharger base tune for the LT1 and it was not impressive. They essentially brute forced the tune. It is not a tune I would put in my vehicle.

[oldman]

correct me if I'm wrong, ST and LT trims are not affected by WOT, i.e. WOT is open loop?

2nd question, the big red negatives I see on ST / LT are too rich i.e. above the stoi levels x (temp,rpm)table. For instance if the (temp,RPM)table has a vale of 1.1 = 13.36 air / fuel, a large negative in the ST / LT trims would mean the car is running much richer than 13.36. Basically if I see negative numbers the fuel curve in the (temp,PRM)talbe should be adjusted down say to 1.05.

I have a new wideband, the suggestion is to run lambda out vs AF. It is all voltage. Can you shed some light on the advantages of mapping labda vs AF. I'm old and only think in AF.

[oldman]

Originally Posted by cellsafemode

did your cai retain the same diameter tube as stock with airflow regulators to reduce the turbulance of the air moving across the sensor like in the stock box?

I believe it is the exact same diameter. I can check this weekend.

A short debate in the Camaro warranty I left, was hinged on this. The stock airbox has a sharp bend before the MAF, the MAF has two cast in flow vanes, which makes sense due to the sharp bend. I pointed out the LS1 had an even sharper bend and had a honeycomb straightener in the MAF. (Some guy said I was wrong, but we all know the LS1 flow path between filter and MAF). Well the CAI CAI it is a straight flow path between filter and MAF. In this case I see less reason to have a flow vane. That said it would be my opinion that for $400. CAI CAI could have designed in the exact same vanes giving the exact same area.

I've been meaning to purchase a new stock lid and either use the stock MAF cut from the lid or cut the vanes out and insert them into the CAI CAI tube pretending to be a MAF. I want to leave no stone unturned.

this is a long term process as I believe LT trims are reset by disconnecting the battery. It will takes weeks and I'll probably need help to determine how the CAI CAI is affecting LT / ST.

I can tell you this: CAI CAI, MSD intake and Cat bypass will throw lean codes. That is 100% sure (stock tune with the rear 02 working but programed to not throw codes).

[Tuned Camaro]

Originally Posted by oldman

correct me if I'm wrong, ST and LT trims are not affected by WOT, i.e. WOT is open loop?

2nd question, the big red negatives I see on ST / LT are too rich i.e. above the stoi levels x (temp,rpm)table. For instance if the (temp,RPM)table has a vale of 1.1 = 13.36 air / fuel, a large negative in the ST / LT trims would mean the car is running much richer than 13.36. Basically if I see negative numbers the fuel curve in the (temp,PRM)talbe should be adjusted down say to 1.05.

I have a new wideband, the suggestion is to run lambda out vs AF. It is all voltage. Can you shed some light on the advantages of mapping labda vs AF. I'm old and only think in AF.

WOT does not affect trims. But positive trims at the time you go WOT can affect WOT fueling. If the trims are maxed out negative the ECM thinks the AFR is too rich and is pulling fuel based on the primary O2 readings. Make sure you O2 voltages in front are constantly oscillating up and down during part throttle. Send me a log if you aren't sure.

Correcting for closed loop fueling calibration is fairly time consuming. I would have to create an entire post on that.

Think lambda not AFR. Lambda is fuel independent. AFR is not. Lambda for stoich is 1.0 no matter whether you are running E0 or E85. A lambda less than 1 is rich. A lambda greater than 1 is lean.

[Tuned Camaro]

Originally Posted by oldman

I believe it is the exact same diameter. I can check this weekend.

A short debate in the Camaro warranty I left, was hinged on this. The stock airbox has a sharp bend before the MAF, the MAF has two cast in flow vanes, which makes sense due to the sharp bend. I pointed out the LS1 had an even sharper bend and had a honeycomb straightener in the MAF. (Some guy said I was wrong, but we all know the LS1 flow path between filter and MAF). Well the CAI CAI it is a straight flow path between filter and MAF. In this case I see less reason to have a flow vane. That said it would be my opinion that for $400. CAI CAI could have designed in the exact same vanes giving the exact same area.

I've been meaning to purchase a new stock lid and either use the stock MAF cut from the lid or cut the vanes out and insert them into the CAI CAI tube pretending to be a MAF. I want to leave no stone unturned.

this is a long term process as I believe LT trims are reset by disconnecting the battery. It will takes weeks and I'll probably need help to determine how the CAI CAI is affecting LT / ST.

I can tell you this: CAI CAI, MSD intake and Cat bypass will throw lean codes. That is 100% sure (stock tune with the rear 02 working but programed to not throw codes).

I'm a little concerned your negative trims aren't right. Shoot me some logs with part throttle O2 voltages and trims showing. We may need your wideband to determine what is going on.

[cellsafemode]

Originally Posted by Tuned Camaro

The MSD intake by itself will be accounted for pretty well by the factory calibration as it is post MAF. Even adding the cat delete pipes is going to do fine. BUT... putting a cold air intake on with those mods will definitely warrant at least throwing a wideband on the car and checking to see where things are at at WOT. The cold air intakes absolutely will throw off your MAF transfer function unless a lot of work was done to ensure that the stock and cold air MAF outputs match pretty damn closely (unlikely).

The driver demand torque tables, at least within the context of what we have access to in HP Tuners or EFI Live, are really only used by the ECM as essentially torque limiters. At pedal % and MPH I want the car to produce X ft lbs of axle torque. They really don't change the fueling calibrations.

The factory calibration (i.e. stock) has to accommodate every single possible scenario one might face. Low octane fuel, high elevation, low elevation, cold, hot, etc... it is close but is not perfect in delivering maximum performance. Tuning is needed to maximize it as well as adapt optimally to your modifications.

I've seen a 2014 ProCharger base tune for the LT1 and it was not impressive. They essentially brute forced the tune. It is not a tune I would put in my vehicle.

So basically anything that relocates the maf sensor (even if the diameter of the tube it's in is identical to the stock and the air straighteners are identical) should be checked with a wideband to see if it is reading the same for the same throttle positions at part throttle to be sure tuning is not required. Otherwise tuning is probably required. correct?

I'm still not sure i'm understanding how the driver demand torque tables factor in. If I do a mod that improves performance, wont these tables over time correct so i'm no longer exceeding the target torque or is that something that just wont ever happen?

For instance (completely made up numbers), at WOT the torque table says I should produce 200ft-lbs of torque. But after a bunch of mods I'm doing 220ft-lbs. Wouldn't these tables cause the car to correct over time to produce 200 again? If not, i'm not sure I understand what their purpose is.

[Tuned Camaro]

Regarding the MAF... it would be best to verify the MAF against the WB. Straighteners on a non stock tube may get it close but it doesn't take much change in airflow path to skew the MAF. You'd have no way of knowing without checking.

Yes if the ECM calculates the torque output to exceed what the table calls for it will attempt to limit the torque. If the ECM is not applying any reduction don't change the tables. And if you do bump them only as much as needed. HPT is likely only giving a sliver of all of the available tables so the dependencies are truly unknown except for those at GM and maybe a few lucky individuals.

[cellsafemode]

Originally Posted by Tuned Camaro

Yes if the ECM calculates the torque output to exceed what the table calls for it will attempt to limit the torque. If the ECM is not applying any reduction don't change the tables. And if you do bump them only as much as needed. HPT is likely only giving a sliver of all of the available tables so the dependencies are truly unknown except for those at GM and maybe a few lucky individuals.

So basically, without modifying this torque table, pretty much anything that improves power beyond some tolerance for the torque value in this table will be nullified. If not immediately then over time.

I'm just wondering what happens then with various tunes and products that dont modify this torque table where they show a dyno chart of 20ft/lbs of additional torque above stock - a week later after driving around. Would they show the same gain or would it look nearly stock then? Are the requested torque table values well beyond what you'd see in anything but a situation that would break engine components? Or does it not apply at all during WOT?

[Tuned Camaro]

Bolt on mods aren't going to push you into any area that will be limiting torque.

[seric16]

Thanks for the info Tuned Camaro! Software Engineer here; looking to jump into the tuning world!

[oldman]

Just got my Mishmoto, I have a grunt tune of 5 percent rich across the board and cat reporting turned off. I'm actually quite happy with it. stock tune would throw lean codes with: cai, msd intake, front cat deletes. No codes for me in many weeks.. 6 or so.