Tacoma - OVTUNE - VFTUNER - Update Info and Original Development

few things:

further testing little tweaks.
regarding anyone getting any of that surge on take off where it feels like the throttle opens more after about 1200-1300 rpm, I have smoothed this area and the transition now is seamless.
it's based on tables that request / limit engine torque based on engine temps / throttle position. These tables are..consider them "4D" because they all work and interlock within eachother and work along with inputs from 2 different sensors.
The more I mute them, the worse the response gets. The more I "open" them, the better response you get.
Regarding other surge feeling quirks, one specific with the rpm and engine revving when you turn the wheel. I cannot change this. I tested by flashing back to stock and confirm the stock tune does it.
changing it when you turn the wheels too hard the engine doesn't correct for it and stumbles.

Regarding some trucks experiencing any fuel cut @ the limiter (during shift). It is possible to hit the fuel cut, although I cannot get my truck to do it some people have said theirs does and has done this even before 1.03.
I suspect this has to be a result of some modification change, or lack of modification that other trucks have? The reason is shifts are controlled by gear + calculated torque + tire/ wheel speed.
conclusion would lead me to think that trucks that are able to actually hit the fuel cut have different tires or wheel size? It's the only part of the equation that is changeable.


regarding any small shifting quirks. Understand that I worked for a long time on the development of this tune to do quite a few things:
- make shifting as smooth as possible with great response for each gear
- make the first 3 gears tailored to help with city driving without big impacts to mpg
- reduce lugging around in high gears unless you are very lightly cruising
- tailor accelerator pedal angle to expected shift RPM (by torque)
and the biggest one of all is removing Transmission "smart" learning features. The thing is we are all doing this and driving the truck on transmission maps that it was not intended for. The transmission was intended to "learn" (learn to be brain dead. but regardless). muting this isn't exactly OEM design, so while the new features work really well and do what everyone asks, there are completely separate sets of tables in control based on if you are in gear 1/2/3 or gear 4/5/6. The cross-over from gear 3-4 changes to a different torque table pull request. So I have done everything I can to make it as smooth of a transition over as possible while muting several things to make the transmission actually act like a transmission.

 

Thank you Mat. Excellent work.

 

My truck is driving like this too. Stock DCSBOR. Flashed 1.03 ECU & TCU and let idle 30 min and drove great at first. Almost like learning is back. I might flash both again and monitor

 

Personally,

A little armor weigh (300lbs er so) and slightly bigger tires and so far this thing feels amazing. I came home from the store and this Audi wanted to play. I held him nicely. Very impressed, although I would not do this normally.


Props @OVTune

 

This sounds like it had been a real pain to fix. Why did Toyota do this.... i can only think for emissions and fuel economy. But they could have took their time and did it right..

 

Well like @MOC221_ mentioned to me once, @OVTune had noted once that there was so many variances in behavior across multiple trucks with the same ECUs, etc, that perhaps Toyota came across this issue too and it was just easier and cheaper to nerf it into the ground to create a decent enough driving experience across hundreds of thousands of trucks, rather than putting in the time and effort to fix it all. Who knows, maybe a deadline was coming up and they said screw it

 

The only thing I’ve changed on my truck is the rims and tires.

16X8 SCS Ray 10 Rims
265/75/16 BFG K02 Tires

I’m aware of the RPM bump when turning the steering wheel.
However what I’m experiencing is a lurch forward followed by surging RPM’s 500-1200pm up and down going forward or reverse.
The shifting seems off and at times alittle rough. Definitely not the same experience I had with my first go around with 1.03 91.
What I’m trying to figure out is why the different experience after flashing back to the 91 tune.

 

@OVTune told me not to flash again. I’d sit tight for him to address this.

 

04B02, or 04B03?

well one thing I have been recommending is that everyone should stop flashing and changing tunes all the time. the KCS control, fuel trims, ignition trims, idle learning it all takes a long time to set and once you flash everything resets.

 

04B03

 

I have the same calibration, but I have only flashed 1.03 once (ECU and TCU). My truck is now quick to shift into OD gear with in town driving to get that 1100 rpm lugging sensation. Also harsh upshift and multiple misfires when applying throttle from light load to heavy load. Not enough to cause CEL. At low speed in town I will get 3 responses from one throttle input, almost like the transmission shifts down a gear, then TC locks or unlocks, then truck shifts back up a gear all within the blink of an eye.

 

I’m kicking myself because the first time I flashed 1.03 it was damn near perfect.

F@#K!

 

@OVTune when can we expect an update with the tweaks to correct the issues you’ve described above

 

very soon. As I am working on a few other touch ups.

 

Are you still gonna send over something for me to try?

 

yes.


here is a brief explanation for everyone of what I am now working on to bring even finer control and smoother power delivery to the truck.
Below is one of toyotas stock tables, from the information and testing I have gathered so far this works in coordination (in real time) with 15 other maps
which control throttle to airflow request based on engine temp and requested torque (gas pedal). This is what I am referring to as the "4D" table

I've been working with the MT guys a bit making fine corrections to this.
below you can see on the image, low RPM Dead zone, then the spike up after 3500 rpm, then down, then peaks up top. (one of 16)
These are what cause your "VVT kicks in at 3500" feeling
except this map is done the opposite. I won't go into to deep of explaning them, but thanks to the MT guys getting me tons of data I have a much, much better version of this.
Properly tuning these are what really transform the truck.

so for example you floor it in 1rst gear... ECU uses request torque, vs ignition..valve timing, airflow mmeasurement to load... comparison to limits table, power reduction, you don't go anywhere.

(higher = less response)

 

Ordered mine today!!!!

 

@OVTune I have 04B02 and having the same issue with the surging as ThatOneTaco. I have 275/70/17, TRD CAI, Spec-U exhaust and about 400 lbs of extra weight from bumper, armor ect.

 

All of this talk is making me anxious all I need is the license key

 

Mine is an auto with 4:88 gears and 33s is this enough of a change in gear ratio to affect the fuel cut because its calculating torque? I was going to order the kit today but noticed your post.