Uptune the detuned SR

Crzy how the muffler is bigger than our gas tank

 

ya thats universal

 

There was someone here who upgraded to the larger tank. Wonder if he was able to get the fuel gauge to self calibrate. Can’t find the thread anymore

 

an option ill be open to down the road

 

Here's my story and how I ended up trying to revive this thread. I bought a 2025 SR Tundra about a month ago. I came from a GMC so I was out of the loop on all things Tundra and wasn't aware of the all the prior differences between the SR and SR5. While test driving I asked the sales guy about power specs. He told me the SR had the same I-Force drivetrain as the SR5 and that is produced 389 hp and 479 ft lb of torque. I liked the idea of saving thousands and didn't think the lack of power seats and drive modes was worth the added $$$. After all the truck I bought was still a crewmax 4x4 and I actually favored the de-chromed look over the SR5. Additionally the options on the lot were limited since it was so late in the year and the 2026's hadn't arrived yet. So in my mind win-win. Then I stumbled upon the detuned aspect of the truck and I felt like i was misled by that salesman and ever since then I've been researching ways to boost the power without voiding my warranty. In fact, the dealership I bought from included a lifetime powertrain warranty so I'm stuck for life. I wish I never learned this because prior to figuring it out I loved how powerful the truck felt compared to my old 5.3L ecotech V8. Now it's in my head and I can't get it out. Has there been any developments on "uptuning" the SR?

 

Why would you use 93 octane when it doesnt require it. If the ytruck was tune for 87 then you are just wasting money...

 

IF you are really wanting the power of a SR5 there is stuff like this out there just search

https://theyotagarage.com/products/...VOBnNpiuNRr-c3gzPHVCjbVPj1wnMoitZhhzhOneK51Zz

 

While the vehicles are tuned to allow for using 87 octane, running higher octane pump fuels allow for more ignition timing. This is well documented. More ignition timing allows for more power under the curve. The vehicles aren't necessarily going to make any more peak power, but will certainly allow for more low end and high load power. Any tuner is going to require 93 octane for this exact reason.

Aside from that, premium fuels have premium additives to clean the motor. This is also well documented by Lake Speed Jr.

 

This is the crux of this thread: whether or not this tuners will work on a detuned SR, and whether or not they will produce the same power as an SR5. Tuning boxes usually alter fueling and ignition parameters outside of the ECU's view, hijacking the signal in and out to produce the extras power while keeping the ECU happy. If you have a tuning box that adds 40 HP to an SR5 that makes 430HP stock, is it going to add 60 HP to an SR that makes 390 HP stock, or will it add 80 HP to the SR motor and make the same power as the SR5? As far as can be determined, the motor internals and peripherals are identical - so it it just the tune that differs? Is the ECU on the SR different? Is it even compatible with the SR5 tuner? Those are the questions this thread seeks to answer.

 

Sorry but JB4 does not alter fueling, nor ignition parameters...none of the boxes out there for these trucks do that. They simply spoof the boost levels the ECU sees. I dont see how you can get an SR to make the same hp numbers higher trims are making if the base tune is weaker. All you'll get is a nice bump in power but no way to know how much more.

If this is a simple de-tune from the factory, then you could/should be able to tune it back up to same power levels with an actual tune or copying a higher trim tune into an SR.

 

That's the point of this thread - how would a tuner affect a detuned SR5. What SHOULD happen may not be what DOES happen. Is the detune simply an ECU flash? Is the ECU different (for example, my 2013 ECU doesn't contain many of the transmission tuning parameters that other tundras do; it's a base model+TRD. My '21 SR5 DOES have the transmission tuning parameters. I can't simply refresh the '13 to add the transmission parameters, I would have to replace the entire ECU). Are there mechanical differences? How can you up-tune a de-tuned truck?

Most tuners (not specifically speaking for this truck) alter fueling, ignition, and boost. If only altering boost, the tuner still has to manage increased fueling, airflow, and changes to ignition timing to accommodate the increased power. Perhaps the factory fuel map will accommodate the increased fueling and air, but perhaps not. Either way, simply adding boost isn't a good way to tune a vehicle. A reputable tune monitors and adjusts fuel and ignition as well.

I really have no dog in this fight as I decided against getting a 3rd Gen SR. I'm purely curious to know.

 

If all this "detune" issue is lower boost, then you cannot get it to make the same HP as an SR5. The box reads oem boost....say 10psi, intercepts that signal and sends back only 8psi so the ecu ups the wastegate duty cycle and ups the boost so it reaches the 10psi being commanded that it thinks its not reaching. So in this instance, you see 2psi+ increase, whatever that means in hp.

Say an SR is limited to only 7.5psi...itll always come in 2.5psi lower than a truck that does command 10psi....thus not reaching the same power level. The ecu will adjust fueling and timing for the additional boost/air flow, not the box.....but it will not make the same hp as a higher trim.

The JB4 MIGHT be able to spoof the signal a bit more to read even lower psi, but that would require custom tuning from BMS which luckily is supported by the JB4. Might start pushing fuel, timing, protect table limits at that point but idk.

I dont think theres an internal difference since SR's are getting the same engine as higher trims...its de-tuned.

All this to say that a piggyback box alone will not get you up to non-SR numbers because it starts at a lower hp raiting and does not affect oem tables.

 

I don't disagree with you.

Again, this thread is about the speculation of whether or not you can up-tune the SR to SR5 power levels - whether that be through an aftermarket box designed specifically for the the SR model, by using an off-the-shelf tuner for all other 3rd gen tundra trims, by reflashing the ECU, or by some other way.

The points you bring up are all valid, and all questions that I don't have answers too (but understand what you are saying). Tuning companies haven't been clear about it, either, and haven't provided an explicit route to tuning an SR.

I'm just here to see if it can happen without an ECU swap (or if that is even possible), out of shear curiosity.. For example, one of the SC'd guys was able to successfully swap his Flex Fuel ECU for a non-FF ECU and with a little bit of tuning, get it running great. He was having issues with the ethanol percentage creeping up without running high ethanol fuel, causing drivability issues. Curious if the same type of route could be taken here.

Another example from the SC crowd - when I pulleyed down my Whipple to make up for lower air density at altitude, the volume of air increased over what is within the normal limits of the MAF. We either needed to do some trickery with rescaling the MAF signal so the ECU would fuel correctly, or increase the intake diameter to slow down the same volume of air as it flows past the MAF. Although this was technically a hardware limitation, the issue could be corrected either electronically via tuning, or mechanically with some new hardware. A new MAF with a broader range was/is also an option.

Just saying that there is usually more than one way to skin a cat - just wondering which ways will work effectively with the SR trucks. What are the specific limitations to power - obviously lower boost, but is that simply a function of the ECU limiting the boost, or some mechanical part or sensor in the system that doesn't have the increased range to handle more boost even if it's commanded.

 

I did a little research on the JB4 fit the tundra: as I suspected, it does alter fueling and timing just as any reputable tuning device would. It even offers several different fuel maps, some of which can be setup to handle e85.

 

it doesn't on these trucks though. Maybe on other platforms

 

You could wait and see if Toyota will release the TRD intakes again. If they do, the instructions tell the tech to reflash the ecu for an additional 30hp over the 389. You basically end up with the TRD performance package, minus the exhaust.

 

So are you saying that on past models Toyota has offered a reflashed ECU?

 

Look up the TRD performance package for the tundra, you can only get it as a factory option now but for a short while you could buy the intake kit and in the instructions, it tells the dealer which software to upload to make the intakes work without a CEL but it’s the TRD performance tune, I know because I bought the intake kit when it was available and had it installed on my truck, the software only works for mid 2024 trucks and newer, it will only work with certain PN ECU’s. It mostly won’t work with older trucks like the

$16 2022-2023 Cup Holder Divider and Hide for 2022+ Toyota Tundra, Anti-Tipping Insert (Matt Black)

2022-2023 trucks.

 

There is a thread in the performance section about tuning a 3rd gen and looks like @texoma has actually tuned them. He might be able to shed more light on the SR debate. Tuning may be the way instead of the plug in boxes

https://www.tundras.com/threads/tuning-options-for-3rd-gen-tundra-stillen-jb4-or-vr-vs-trd.136937/

 

Do you remember where you bought the kit and did you take it to a dealership to get installed? I would assume you have to if they have to upload new software.

 

I bought it directly from Toyota when it was available and yes the dealer installed it and uploaded the software. The kit PN is PTR03-34223

 

Thanks for the info. Are you running oiled filters in it or dry? I've read some things about oiled filters that give me pause because it seems they have a fine line you must follow to prevent too much oil screwing up your map sensors or too less oil letting dirt through. Seems like dry filters are more "set it and forget it".

 

Let me get my hands on it and I’ll tune it for max HP and TQ

 

HELL YEAH!!! now who has a SR and WANTS TO GO FAST!!!!

 

So it begs the question - can you get more power out of an SR to take it up to tuned SR5 power levels? Or it is 45 HP/75TQ on top of the detuned SR power levels?

 

The power increase was based on the SR5. So with tuning an SR, would be even more of an increase over stock numbers.

 

Not an SR but very interested..

 

So in theory, could you copy a base stock tune from a SR5 onto the SR?

edit: I also don't have a SR but this is an interesting topic.

 

thats what Im thinking too.