2AZ-FE Ignition Timing Advance/Retard

[XEusioN]

Has anybody here hooked up an ODBII scanner to their car while driving to detect timing advances/retards, especially on switching to higher octance fuels? Butt dyno says the car feels a bit stronger on 93 vs 87, but the butt dyno is also phased by the placebo effect

Just looking for some hard proof, if anyone has tested this yet, let me know

-James

[i20solara02i]

do you have an i4?

[XEusioN]

Yep

[Turbosolara]

for sure 93 will had higher power because it cause less detonation and the ecu will be able to advance the timing. if lot of detonaiton happens (in lower grade of octane) then the ecu will try to retard the timing to protect your engine.

some retard people might argue that the econo engine is made for you to pour in 87 octane. but keep in mind it has vvti and moderately high compression, higher octane is always recommanded. Also, the user manual also tells your to achieve higher performance, you should pour in higher octane.

for the newest accord v6. they dyno tested and found 91 made 15hp gain from 87.

[XEusioN]

Regarding that Accord V6 power gains, thats a subject that's been speculated on for a long time. USAToday reported along time ago in an interview with a Honda powertrain engineer that premium would help you pick up an additional 10hp/10tq. Unfortunately, none of our 7th gen AV6 members on V6P have been able to duplicate these results consistantly. Some dyno tests that were done back to back including SAE correction, complete fuel tank drain, and ECU reset/relearn periods showed an improvement of 5-8whp (10chp-drivetrain loss.)

Big reason why I'm concered, is on my old 2002 Accord V6, that engine actually LOST power when using anything higher than 87 octane fuel. For example on my old accord, there was NO knock sensor and the car would not adjust for any higher octane fuels. Basically Honda really screwed up on the J30A1.

I also understand how knock sensor monitoring and adjustments work, but what I want to know is, has anybody yet to actually document a real change in ignition timing via an ODB2 scantool or replicated these gains on a dyno? Because the theory is solid, but is it applied in these motors?

[Turbosolara]

I am sorry i didnt answer your answer correctly. but my theory is that knock sensor will fix the timing according to the detonation. and in toyota user manual, they told you to use premium to acheive best perofrmance (i believe this implies that the timing does change). I think in your 02 accord user manual just suggest 87 octane is that correct? your accord was tuned for 87 octane but i think most of toyota motor is tuned for 91 but sustainable for 87.