2GR FKS Toyota Tacoma - Bringing new life to the Tacoma Platform
OrangeVirus Tuning has officially released our ECU and TCU Calibrations for the 2016+ Toyota Tacoma 3.5L.
The 2016+ Toyota Tacoma is featured with Toyotas all new 2GR variant platform engine dubbed "2GR FKS." The engine is a 3.5L V6 with dual intelligent camshaft control (Variable Valve timing intelligence) with variable Atkinson mode. The camshafts allow for a wide range of manipulation to the amount of valve opening advance requested based on engine load and engine speed. This gives the engine the ability to create an atkinson effect at low loads and low RPM, creating enhanced efficiency. This engine also uses a feature that is starting to pop up on newer engines, cooled exhaust gas re circulation (EGR), an added efficiency bonus.
The engine uses Toyotas dual stage intake manifold design which can create variable intake runner lengths (short or long) to enhance useable torque throughout the rev range. The exhaust manifold is integrated into the cylinder head and utilizes a single exit port per bank. This 2GR variant uses D4-S direct injection technology and comes standard with forged internal components.
Toyota spent careful time to develop and entirely new cylinder head to mate to this 2GR platform. However, is this engine really as good as Toyota makes it out to be? We have some questions, and concerns, and what we have accomplished so far. Lets talk about them...
First lets start with the horsepower ratings. There are several different horsepower ratings for this same engine depending on the chassis. The Tacoma gets 278HP, while the camry gets 306, and the lexus version gets 311HP. The difference in Maximum achievable RPM from the tacoma @ 6100, lexus @6300 and Camry at @6600 is nothing special. A few hundred RPM rarely makes up a difference of 23 horsepower (and only a 200 RPM difference with the lexus chassis and the tacoma). However, in time we will confirm this.
So what's the secret sauce? Is there any?... Well we took a deep look into the 2018 Toyota Camry Calibration and the Toyota Tacoma Calibration and compared side by side. They are nearly identical. Fuel targets are similar, almost everything, except a few key differences. The intake valve timing advance and the ignition advance (relatively 2-3* more advance on base tables from what we gather). Wow! We found it! here's how Toyota is gutting the Tacoma (for no good reason may I add!!). But... we were wrong.
We Dyno tested the exact targets the Camry uses on the Tacoma, and we used 91 octane just to eliminate any "potential" set backs in power. We gained a whopping 2-3 horsepower in the mid range. Nothing. How Disappointing.
We attempted further with the Camrys ignition advance targets. A few extra horsepower was gained. In Total, under 5 horsepower. We plan to dissect the Camry ECU further and do more testing, but from what we can gather so far there is not that much variance in them that creates a 20+ Horsepower deficit.
Here is the difference between the Camry 3.5L and Tacoma 3.5L Valve timing tables. Notice the Camry uses extra advance, but top end targets are relatively the same. So is the Camry picking up all this extra horsepower simply by extending the rev limiter? We think not. But that the next logical step for us to take.
The image on the left is the Toyota Camry 3.5L 2GR FKS Valve timing. The image on the right is the Tacoma. Did Toyota just get lazy, or were they rushed when they Tuned the Tacoma? They focused on high load and low RPM, and then just threw a flat advance through the entire mid-range. It's not hard to see which platform Toyota spent more time developing. (hint: it's the Camry). But even still...where's that magical horsepower?
Luckily, we can fix what Toyota failed at. Creating a clean Calibration for the entire range of RPM and load. We Spent a few months and may rounds of dyno and street testing to capture the data required to accurately time the Valves on this engine to maximize torque, without causing detonation or pre-ignition. One thing we have experienced when tuning these new engines being made with "Atkinson" modes, is that the elevated static compression brings with it an unwanted guest. Pre-Ignition.
Ignition Timing Control
So, now that we have talked about Toyotas Camshaft timing...lets talk about the next step in making horsepower. Ignition Timing. The Stock 2GR FKS Ignition Timing maps are so ugly I ask that small children please leave the room before you look at the images below. This is not a joke. This is an actual OEM Ignition Map from the 2016+ Toyota Tacoma.
I have two questions, who did this and what was the point of such a table?
Several customers of ours during our calibration development process told us that they had experienced problems on the stock tune with shuddering, stuttering, and misfiring. Several customers had to purchase their own Tech-stream accounts to log the vehicles when dealerships were little help. These Data-logs show the ECU counting several counts of misfires on various and all cylinders throughout a normal driving cycle. Now before we go further, we should explain that all engines misfire sometimes. That's why ECUs (engine brains) these days accurately track misfire counts. But the Tacoma is something special. In a 10-15 minute driving cycle some of these trucks were logging 15, 20, 25+ Misfire counts on various cylinders. This is not normal.
Toyota has a "fix" for this by replacing the Crankshaft position sensor. Does this help? Yes. Does it fix the problem? We think not. Once again we are able to clean up this mess through aftermarket calibration. We go through all of Toyotas Ignition logic, Log the data, Log the outputting ignition, and make changes in problem areas. During testing we were able to make changes to ignition that reduced Misfire counts by more than 90% from OEM. From more than 10 misfires in 5 minutes to less than 2 in an entire drive cycle. We can do this on 87 octane and 91 octane.
How? By fixing that mess.
Our ignition recalibration fix really helps smoothen ignition timing and alleviate some of these misfires and stutters that the stock calibration has that cripples drivability.
But our work was far from over.. making changes only to fueling, ignition, and valve timing is tuning of the past. These trucks, especially the automatics, have variable learning modes that encompass the entire calibrations logic. There are progressive multipliers for ignition, progressive maps for shifting and progressive map shuffling for Transmission output shifting torque.
What does this mean? The truck is unpredictable.
The automatic transmission version of this truck has extra issues that we can't completely cover, but what we do know is that the truck uses a 16 way shuffling scheme that changes shifting over time. There are 16 different "modes" or settings, paired to over 100 different upshift and downshift control maps that tailor to calculated torque to complete a "shift" to the next gear.
But Toyota got a bit lazy here too. (in our opinion). There are well over 100 different Shift control maps and more than 16 for each gear just for up-shifting. However 90% of these maps are identical! So The Truck will use base up-shift Parameters, and change the way it shifts using these Transmission output maps. Horrible!
Once again...we figure out how to alleviate this shifting disaster. Our TCU Calibration changes how the Transmission shifts, when it shifts, and the desired Torque values used to complete a shift and calculate shifting time. This makes the gears actually useful. This makes it where the Transmission will properly skip a gear seamlessly on downshift to get you up to the speed you request when you press on the gas. Rather than driving in 6th gear at 35 MPH and stomping on the gas and "nothing" happening, our TCU calibration changes how the truck shifts, when the truck shifts, and makes it actually driveable!
Here is an example of the Tacomas Transmission Calculated torque maps for shifting. There are 16 of these maps. You don't know when or where the truck will shuffle from one to another, and you will never be able to accurately predict how your truck will shift from one drive to the next.
The difference in these maps can transform the truck from a beautifully shifting machine, to something that does not know what gear it wants to be in, or even where it is in space-time. (it's really that bad).
Did I mention that Toyota already has 2 OEM Calibration updates to try to fix this failure of a transmission tune?
Our Calibration not only changes this, it alleviates most of these transmission shifting problems AND gives you the option to select from 3 completely different shifting modes that lets YOU, the DRIVER, know what the truck is doing and gives the control back to you!
Maybe Toyota is lazy for a reason (don't change what we know works) or maybe they know something nobody else does, but in our opinion their calibrations are lacking in the fuel delivery department. *Most* Vehicles these days use accurate 02 feedback for full time closed loop Fueling control (always on target fuel demand). Not Toyota though. They are still stuck in the days of Open Loop junk. The days of Open Loop Fueling control are over Toyota!
A quick explanation of the difference. Closed Loop control means that the ECU is always watching the sensor feedback (like the reading on the O2 sensor) and adjusting the tune on the fly to ensure the fueling is "spot on" all the time. That means when you floor it and the ECU targets AFR of 12.67, you get 12.67, every single time. ECUs these days are actually quite good at this.
Open Loop is what ECUs used to do. Basically Open loop is a switch that changes from using feedback, to using an algorithm and ignoring feedback. So when you stomp on the gas pedal, there are a few switches. RPM, Load, for example. When RPM goes above 3000, and Load above 0.75, switch to open loop. (use an algorithm to calculate fuel, and screw what the sensors say!). This means that fueling is unpredictable! The Tacoma uses this strategy and power demand enrichment is so rich you're wasting gas by going over half throttle in this truck. Fuel delivery is so rich it maxes out the stock sensors ability to read the O2 sample. This is 2017, I thought we care about our environment Toyota. (I think Toyota just expects the catalysts to pick up the slack of the stock calibrations weak fuel logic).
Thankfully we are able to completely changes this. We slightly lean up the fueling, make more torque, no knock, and use less gas at the same time. The difference is substantial. From AFR's richer than 11.0 (something a turbocharged car would target) to around 12.6-12.5, leaner and meaner. We are able to do this by exploiting the D4-S control logic in a positive way. We change the calculation rates of the Direct injection system so that it does not dump so much fuel on power enrichment. A simple fix with a big difference.
For reference, here is one of the Tacomas OEM Fuel Calculation map. It may *look* Ugly, but in all honestly this is not outside of the norm for a Calibration. There are several other maps that compensate and apply factors to this map to calculate the final fueling result that enters the cylinder.
Nothing surprising here when you read the stories of "throttle lag." This is pretty common on newer vehicles with Drive-By-Wire systems (electronic throttle). Changing throttle is actually quite simple. We have complete control over throttle opening / angle targets, and we enhance this in our tune.
Even better for the automatic which uses Toyotas "throttle intelligence" for torque control, we are actually able to remove Toyotas OEM Throttle restrictions that limit torque in low and mid range RPM, the difference being substantial. Toyotas OEM code does NOT let you go full throttle in lower RPM in the automatic transmission. When you floor it, the stock code does not say "open throttle" it says "downshift" or "limit throttle." We have seen this on the dyno where 4th gear in lower RPM will either force a downshift or force the throttle to limit to around 30-40%. Taking away available power. (we fix this!)
Stock Throttle angle to Accelerator Angle Throttle map (before mode changes like ECT, or any throttle compensations applied (like Torque calculation modifiers) )
What does this map tell you? If you want the truck you move, you better FLOOR IT.
Bonus... Remember when I said Unpredictability?
When you start your Truck in the morning, Which step of the learning process is it on? Here look at the code.
The world will never know.
See more about our development process at the Tacoma Forums :