I’ve been covered up with work, house painting, child’s birthday, and more… haha.

I’ll see if I can burn some Friday night time to give a creative comparison based on where the car is in the rpm range.

 

This isn’t very creative, but allows some comparison. I took out any information that was not what I call “fake 2nd gear.” This is because I have been using the CVT in 2nd with paddle shift in an effort to keep consistency. Also, because of the way I have to gather data, it is very hard to get the exact same RPM for each test. I am also rounding RPM to the nearest 50.

 

All good. Appears timing is a few ticks north, so that should translate into increased HP.

 

Working my way toward full 93 octane in the tank. Maybe get another 1-2 degrees. Currently the math worked out to 91.2 octane, if my memory is serving me correctly. If I fill up when I usually do, and use 93 octane, It will likely be
8gal x 93octane = 744
2.6gal x 91.2 = 237.12
744 + 237.12 = 981.12
981.12 / 10.6 = 92.56 octane

I'm super intrigued by how aggressively the car pulls timing at 5300-5400 RPM. It seems like an engineering decision to really hold the car back, save the CVT, or something.

Car is around 7 years old, single owner, 75,000 miles, have not adjusted valves, or changed plugs. The short trim does say it's adding fuel. I am not a tuner, but my understanding of short trim is that the car's systems are running well enough that the car sees opportunity to add fuel to it's original plan.

Edit: I made my "intrigued" comment above, but in reality, I also don't know what the VTEC system is doing. I'm sure ti could be doing something aggressive with the cam and the timing needs pulled back. It has been 7 years since I drove my 6spd LX, and I cannot remember if the VTEC was aggressive around those RPMs. I've heard the slushiness of the CVT, even when using the paddles, can really hide the CVT feelings.

 

6 speed isn't super aggressive with VTEC. The torque is what gets me. I may be wrong but I believe 4k at certain throttle % is when VTEC kicks in, yo.

Worth noting for anyone adding this to the equation, recently I adjusted valves, plugs and cleaned intake valves and essentially cleaned all throttle body moving points (even under plastic cover. Warm weather isn't great for pulling but it seems that with all the rain the IAT has been significantly pulled down and I'd be willing to bet with all the moisture timing as well. It feels as if I have 93 octane in it now and there is a significant, noticeable difference in 77°F + heat pulls vs. 75 ish or less with rain. Maybe 10-12 hp. I do believe IAT and density are the key as opposed to fuel choice for maximal cost benefit but don't let me stop you. Also thanks for sharing.

 

Okay... updates... Been a while as life got in my way.

Two key takeaway.....

1. The timing will advance with higher octane, but I don't have enough data to say if 92-92 is better than 91.
2. The fact that it drops to 14-16 advance around 5400rpm and higher may be a good thing, but I have not had time to research. A little research told me that 14-16 is a widely known tuner knowledge for the ideal advancement at high RPM. The heat and rate of compression cannot handle those big advances at lower RPM.

Disclaimer - I pulled a few data points that seemed like outliers. I can tell that if I even barely pull my foot off the floor or the car goes to shift, it expects something different with less fuel and advances the timing quite a bit.

 

If I were to say.... 87 vs 91+, the results would be 91+ every time will give more timing advance. Now to say that the car is making more horsepower would be mostly an assumption for me personally that more timing advance means more horsepower created, or more energy is being found in the fuel source.

What I can say is that I probably have not floored a car this many times in this short of time, and I 100% believe that after 4500rpm the car is far smoother or happier at those RPMs, especially that 6500rpm range.

More to come, slowly but surely. I will continue my pursuit with 93 octane, using about the same location. I am currently up against 97-ish degree temps and that makes it hard to replicate each aspect of my semi scientific methods.