2026 4Runner TRD Sport Dyno Results (Stock vs Tuned on 86 Octane)

[CAMTuning]

I can appreciate your POV & perspective on this topic. As I said in a previous post, I'm not a gearhead or well-versed in high performance automotive applications. With that said, I'm no meathead either & this is a topic that has captured my attention & curiosity. I've thought alot about this because I want my own 4Runner to have very limited problems & keep taking me places for the next 20+ years.

I personally do not believe that the factory tuned stock engines in the '25-'26 4Runners are tuned by Toyota to deliver more horsepower from commercially available gasolines with more than 87 octane. It's just not tuned from factory to take advantage of the higher octane. The turbos make very little to no difference regarding the higher octane because the engine is simply not tuned to benefit from higher octane...unlike the '25-'26 Land Cruiser HV which does require 91 octane or higher.

Quoting ChatGPT now:

“ Important nuance (this is subtle but critical)
Some turbo engines do dynamically increase power with higher octane.
But only if:
The ECU has octane-learning maps
And is programmed to advance beyond the baseline
Toyota did not do this on your 4Runner’s 87-octane calibration

Final, precise answer
Your 4Runner’s ECU:
Is not knock-limited on 87
Does not advance further on 91
➜ 0 HP gain
Land Cruiser’s ECU:
Relies on higher octane to maintain performance
➜ Lower octane would reduce HP, not increase it”

What I do believe is that aftermarket tuning can & does increase HP if tuned to benefit from higher than 87 octane gasolines...though I do wonder what that does to the lifespan of the engine as a whole.

With that said, the stock engines in this 6th generation of 4Runners, both Non-Hybrid & Hybrid powertrains, are not tuned by Toyota to deliver more HP when using more than 87 octane gasolines.

Also I missed this one earlier. ChatGPT gets it wrong a lot. These ECU's do have an octane learning- it's called the KCLV, or Knock Control Learned Value. I made a post about it here:
https://www.4runner6g.com/forum/thr...nner-like-we-do-at-camtuning.8232/post-100133

I too quoted chatgpt here:
" We’re not talking about some generic “turbo engine maybe likes premium” theory. We’re talking about the T24A, which has active knock correction and knock learning behavior. If the ECU is learning around knock and adjusting timing globally, then octane absolutely matters to how much timing margin the engine can carry. "

Sponsored

 

[Scrappopatamus]

Anyone that's read through this entire thread probably has a reasonable cause to sleep in Sunday morning. I've experienced this sort of evangelistic preaching having grown up in a small Southern Baptist church and family. I sense I'm now a better person having realized the meaning of life from reading this thread. Totally off the rails, "Lighten Up Francis"!!! We all have our opinions, but someone scripting a novel for every response always adds the spice. Great entertainment value for sure.

 

[The_Dark_Knight_Forever]

It will be the same 4Runner, same dyno. I’ve already done multiple runs on 86 octane. I always take the best of three since there’s a few hp of run-to-run variation. Also worth noting—the first pull after an ECU flash is consistently lower on this platform, so I don’t use that one.

If Toyota documentation is the only thing you’ll accept, that’s fair—but that also means no amount of real-world testing is going to change your mind. I’m still going to post the data.

On the “skin in the game” comment—I don’t make any more or less money based on what fuel someone runs. A tune on 87 vs 93 is the same for me. The only reason I bring up octane is because of how these engines actually operate. Someone is getting rich on these fuel prices, but it isn't me!

These are high compression, turbocharged engines. They’re knock-limited. Higher octane doesn’t “add power” on its own—it allows the ECU to run the timing and load it wants without pulling back.

And power aside, it’s not just about peak numbers- it's about mechanical sympathy. Lower octane means the ECU has to intervene more often to control knock. Even when it’s doing its job, that’s still added stress compared to running fuel that gives the engine more margin.

Thanks for sharing your insight & personal experience working with these engines. I respect your opinion & perspective. I'll look forward to seeing your data when compiled & posted for all interested to see.

As for my personal opinion, I doubt I'll change my mind. I also don't make up my mind solely on what ChatGPT states as I've proven it wrong on occasion about some things. You did mention it gets things wrong also. I draw the conclusion that Toyota intentionally tuned these engines for 87 octane because they're not being used in a luxury or a high performance vehicle & as such they needed to keep them at a price point consumers would still be willing to swallow. In my mind it makes no sense to produce an engine capable of delivering increased HP on higher octane gasoline but not advertise what would be considered a built in beneficial feature for consumers interested in new generation 4Runners...especially considering the 5th generation delivered only 8 HP less using 87 octane than the 6th generation does using 87 octane. Theoretically the new Land Cruisers (they're all hybrid models) should probably be only requiring 87 octane the same as the 4Runner hybrid models do. For the higher price tag on the LCs one would think Toyota would give the owners' a financial break by not requiring 91 octane or higher gasoline for a vehicle that is practically a 4runner with a different shaped body on it.

This is a public forum after all & differing opinions & ideas are enevitable. In the end, those here are here for the same reasons & are interested in the 6th generation 4Runners. Each is free to make up their own minds about things they wonder about & do what he or she believes is in his or her own best interest.

 

[The_Dark_Knight_Forever]

Anyone that's read through this entire thread probably has a reasonable cause to sleep in Sunday morning. I've experienced this sort of evangelistic preaching having grown up in a small Southern Baptist church and family. I sense I'm now a better person having realized the meaning of life from reading this thread. Totally off the rails, "Lighten Up Francis"!!! We all have our opinions, but someone scripting a novel for every response always adds the spice. Great entertainment value for sure.

It takes more than a few words to explain things especially when it comes to a differing opinion & the rationale. Short replies leave alot open to interpretation and don't lend well when discussing a technical topic. IMO of course.

Sponsored