1GR-FE Tacoma tuning

Just wondering if I could get a little direction in tuning my Tacoma.

First, I can't seem to read and save whatever current ECU program I have installed, even after writing the ECU with the provided updated tune provided by HP. Still getting the "your program is out of date message"

Second my spark retard table seems to start at -3 which I am interpreting as 0 and at altitude ( 7000 ft ) with the timing tables I have set I'm seeing anywhere from -3 to -1.1 in my table. It seems to run pretty good at this but would love to understand this better.

Third I noticed I have a low octane and high octane table. If I built my low octane table for lower elevation timing numbers, and my high octane table for higher elevation timing numbers seeing as I usually run 87 octane all the time regardless of elevation would that be safe? Also is there anything I need to program to make sure the truck automatically switches between the two timing tables based on I assume knock sensor output?

Forth I have my power enrichment starting at 40* and at 1.2 across the table. This seems to work pretty well, but don't know what other people are doing in these parameters.
I only have rear cats and have disabled component protection

Fifth I am wondering if people have modified other parameters such as cam timing and the intake air charge control to get better mid and high RPM power out of the 4.0. after throttle body remapping, power enrichment and timing changes my low end power is great, but seems to still go kind of flat above 2500 rpm, pick back up at 3250, and drop off at 4000. Definitely better than before but if there are any other little secrets to getting more out of the engine I would love to hear them.
Thanks
Chris

Or if anyone knows of resources to buy as a guide, I would appreciate it

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Originally Posted by cjm11083

Just wondering if I could get a little direction in tuning my Tacoma.

First, I can't seem to read and save whatever current ECU program I have installed, even after writing the ECU with the provided updated tune provided by HP. Still getting the "your program is out of date message"

Second my spark retard table seems to start at -3 which I am interpreting as 0 and at altitude ( 7000 ft ) with the timing tables I have set I'm seeing anywhere from -3 to -1.1 in my table. It seems to run pretty good at this but would love to understand this better.

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That is correct, Knock Feedback (KF) defaults to -3.0, which corresponds to no knock (0 degrees retard). When KF is greater than -3.0, the PCM is entering or has entered knock-learn up, which is where you will see Knock Correct Learn Value (KCLV) increase - KCLV is a global adder for timing, and there are three different zones for KCLV (each with a corresponding KCLV value). KF of less than -3.0 can mean that there is active knock retard, but it also occurs if there is a large difference between KCLV values at a zone boundary. If, for example, we were going from a zone with a KCLV of 23 to one with a KCLV of 28, we will usually see KF pick account for the difference (5 degrees), for a KF value of -8.0, which will be decayed over time.

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Third I noticed I have a low octane and high octane table. If I built my low octane table for lower elevation timing numbers, and my high octane table for higher elevation timing numbers seeing as I usually run 87 octane all the time regardless of elevation would that be safe? Also is there anything I need to program to make sure the truck automatically switches between the two timing tables based on I assume knock sensor output?

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Briefly, yes, that's safe. Adaption ultimately occurs via KCLV, provided your timing tables don't force excessive learning at low load, it will largely handle the corrections on its own - there are ways to make it behave better with regard to how quickly it will learn up/down, but the stock behavior is more than enough for most.

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Forth I have my power enrichment starting at 40* and at 1.2 across the table. This seems to work pretty well, but don't know what other people are doing in these parameters.
I only have rear cats and have disabled component protection

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You'll get varying answers on those items, including on disabling component protection, but they are not abnormal numbers - you may raise enrichment some with an eye towards fuel economy without sacrificing drivability or durability, particularly if you're at elevation.

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Fifth I am wondering if people have modified other parameters such as cam timing and the intake air charge control to get better mid and high RPM power out of the 4.0. after throttle body remapping, power enrichment and timing changes my low end power is great, but seems to still go kind of flat above 2500 rpm, pick back up at 3250, and drop off at 4000. Definitely better than before but if there are any other little secrets to getting more out of the engine I would love to hear them.
Thanks
Chris

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The impact of ACIS is pretty simple - any time it's active, there is a benefit to torque, at the expense of increased pumping losses and concomitant fuel consumption at part throttle. As such, lowering the entry threshold (Engine -> Airflow -> Charge Motion Device -> ACIS -> High TPS) will make the truck feel more responsive. For more responsive driving, I recommend lowering to a point that it's just below activation at typical cruise speeds on flat ground. Doing so ensures that it activates as often as possible without a significant fuel economy penalty on the highway. For a bit more fuel economy benefit, I recommend doing something similar, but for the steepest hills you typically encounter - that will still have the activation much lower than it is currently, without any impact to unloaded highway driving.

Cam timing is a bit beyond the scope of a simple forum post, but the basic procedure is this: create 3 versions of the same file, one with unmodified timing, one with additional timing (3-5 degrees) and one with less (-3-5 degrees). Limit your logged channels to Engine RPM, Calculated Load, and Absolute Load with the polling rate set as high as possible, create a graph of Calculated Load with axes of Engine RPM and Absolute Load, then log each file. What you are looking for is the cam setting that has the lowest Calculated Load for a given Absolute Load. The reason for this is that Calculated Load corresponds with Manifold Absolute Pressure while Absolute Load corresponds with Volumetric Efficiency, so we're really finding the cam setting that gives us the lowest MAP for a given VE - written in other terms, that is the greatest VE relative to a given MAP, we're using the rearranged version because Absolute Load is the axis used for cam timing.

From there, you can copy/paste the best cells from those logs, smooth the table, and repeat the test until neither the additional or lower timing maps offer improvement - will take a few iterations.

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Originally Posted by cjm11083

Or if anyone knows of resources to buy as a guide, I would appreciate it

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While the information is Tundra-oriented, and a bit dated now, I have a guide that covers some of these parameters: https://drive.google.com/file/d/1vjg...7USHoswg7/view

Since it's getting out-of-date, if you have questions, just post them here.

Wow, thank you so much. I have a lot of learning to do on this. I will probably have quite a few questions. I have been building a few different programs since I posted this question, and had sort of moved over to the Tacoma world forum for help, got some but not nearly this detailed. I just checked back on this forum today because I didn't think I had any responses. I'm going to review the tune that I've built with this new found knowledge and might reach out for some advice after doing so. Again I really appreciate it.

SlowNStock, could I get a little coaching on timing tables. I have been working on a tune (before I read your above post) and had generally given up on figuring out the octane table vs base map table thing, and just made all three the same adjusting until I got a knock feedback of -3* or less (less negative). After reading your Tundra tuning guide it would seem that is not a good strategy and is basically just limiting the ecu's ability to adjust timing. I have been trying to wrap my head around Toyotas strategy for timing and where I could make meaningful adjustments but it's really just above my paygrade with the current amount of time I have to devote to it. I have been very happy with the adjustments I have made to throttle mapping, transmission shift timing, ACIS points, and power enrichment, but at this point put all timing tables back to stock, and I think it is running better with the stock spark maps than with my more static table approach. I will be starting my cam timing adjustments tonight and plan on adjusting spark after that. Any suggestions on what maps to adjust and how to evaluate results? Also any suggestions on places to just buy a pre-made dyno proven tune that I could then modify to my liking?

[QUOTE=

Cam timing is a bit beyond the scope of a simple forum post, but the basic procedure is this: create 3 versions of the same file, one with unmodified timing, one with additional timing (3-5 degrees) and one with less (-3-5 degrees). Limit your logged channels to Engine RPM, Calculated Load, and Absolute Load with the polling rate set as high as possible, create a graph of Calculated Load with axes of Engine RPM and Absolute Load, then log each file. What you are looking for is the cam setting that has the lowest Calculated Load for a given Absolute Load. The reason for this is that Calculated Load corresponds with Manifold Absolute Pressure while Absolute Load corresponds with Volumetric Efficiency, so we're really finding the cam setting that gives us the lowest MAP for a given VE - written in other terms, that is the greatest VE relative to a given MAP, we're using the rearranged version because Absolute Load is the axis used for cam timing.

From there, you can copy/paste the best cells from those logs, smooth the table, and repeat the test until neither the additional or lower timing maps offer improvement - will take a few iterations.[/QUOTE]

While logging this data, none of the channels seem to have an adjustable polling rate, not sure if I have my table set up correctly.

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Sorry,
Struggle bussing with forum use

Anyone out there willing to take a look at and give me some feedback on my latest program/data log. I am pretty happy with the way the truck runs, mostly want to make sure its safe and am wondering if my long term fuel trims need to be addressed. Any and all tips and feed back would be appreciated
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