Makes sense to me because even more timing advance possible w/ plugs.

 

Exactly. At the time it was the ONLY way to get a gain out of the factory ECU, "tricking" it to advance timing based on the cooler plug and higher octane... Even then like I said, only 2-3whp

The L15A7 is a similar but significantly different engine than the L15A1. Still, I would bet good money that the only way to get a static gain off of the GE ECU (Meaning lasts through a full reset of ECU driving cycles. It's supposed to be even MORE nannying than the GD's ECU) would be the same trick with cooler plugs and higher octane.

 

yup. the 2nd night on regular was called on account of exploded Neon. It was quite comical to see its pressure plate come rolling out of the garage by itself. I think both the crank case and transmission were cracked based on the amount of oil to clean off the dyno. We kinda lost interest after that.

 

I only use regular unleaded fuel and that's about it...

 

Man this is funny lol I run mostly 87 but have occasionally filled with 91.I honestly do not notice any difference in performance or mpg between the grades.

I do however think my hard break in and aggressive driving has in a way created a more aggressive tune from the adaptive ECU.On my 2011 5.0 Mustang there was a difference confirmed on the dyno when tuning with 87/91/E85

On this little bone stock 1.5 Fit 87 is fine and here in California 91 is near $5.00/gal
I will continue to run mostly 87/89 and if I have the extra cash 91

I wish the Flash pro was out for the GE so I could data log and compare my log to others that have babied their cars since new.

 

I reset my ECU the other day when I was installing my horns. Car doesn't feel as good and I've been babying it since then.

It's also been super humid, low pressure, rain, so maybe that's really why, idk.

I wish I knew more about how the ECU adapts to changes, a datalog like you're talking about would be interesting zilla8.

 

And that is your problem there is no insult in saying that your ignorance of the operation of an internal combustion engine make you unable to know that.

"Gee, the gauge shows different timing numbers" tells me that the timing is different, not that it makes any relevant difference

Changes in ignition timing are EASY to understand and comprehend for people that know what they are talking about so it's not an insult it is a statement of fact.

I tried to lead you by the hand and explain it in the most simple of terms so anyone with a limited knowledge of engines should be able to comprehend what happens when you advance ignition timing.

But you are one of those members that has to have it explained very slowly and refuse to believe what you are being taught just to be contrary as your posting history shows.

Very simple do the research yourself and educate yourself on this topic. There are many many books, articles, lesson plans, and websites available
on this very subject do the research yourself so you will believe it because more learned members already get it.

 

Read the above post ^^ as it applies equally to you.

 

There is a simple solution to your conundrum just install a scan gauge, read the instructions on the different engine systems it monitors, and watch in real time what is really going on with the multiple systems controlling your engine performance and the difference using higher octane vs lower octane fuel.

 

Whew at least a few members get it. Using cooler heat range plugs does indeed move the detonation point further so the ECM really really can advance the timing even more.

 

LOL you trust a government agency???

But in this case they are mistaken as members data already submitted PROVES you get more ignition timing in a Fit using higher octane. Are you saying that all the members that reported that are lying?

Regular octane is just fine if you putt putt around time like a little old lady or are concerned about squeezing the last nickle out of your pocket.

But if you are a performance fan and drive hard the benefits of higher octane are obvious to anyone with a scan gauge.

 

To see the effect of octane "where the rubber meets the road" as you say one just has to go to any dragstrip this weekend. There you will see racers gladly (well maybe not gladly) paying out $15.00 yes $15.00 a gallon for racing gasoline at 105 octane.

Why would they pay that if good old 87 works just fine thank you.

Very simple they are knowledgeable enough to understand that the highest octane you can find gives the best performance all other factors being equal.

And why do you think EVERY type of racing sanctioning bodies, that are limited to gasoline based fuels, limit and check for compliance the highest octane rating that can be used legally?

That is because they also know that higher octane improves performance.

That "rubber to the road" enough for you? Nope I'm betting it's not but the rest of us know.

 

Yup a lot of Drag-Fits lining up every weekend fursure

p.s. It's a well known racing adage to use as low octane as possible as the octane enhancers reduce btus.

Racing fuel on the other hand has higher btus. I think that's where you're confused.

 

I do plan on picking up a Scangauge and I do actually know what all those numbers mean I am excited to see what it has to tell me.


A old friend of mine used to put 105 in his Yaris for special occasions not sure how much it helped but it sure smelled good.

 

Again, nothing on this thread shows how much actual difference the timing makes. Yeah, so racers using different engines, that are made to utilize the benefits of higher octane fuel, use higher octane fuel. Wow. Claiming that because I ask for data shows that I know nothing about engines only shows that you know nothing about me.

Again, a scan gauge showing different timing isn't a scan gauge or chart showing different HP or MPG.

 

Laughable if you knew what the heck you were talking about you would know, like most of us, that increased ignition timing is increased HP and wouldn't have to beg for someone to explain it to you.

Like I said take advantage of the many many sources on this subject educate yourself and get back to us.

 

WHAT ...............let me get this straight are you actually trying to say that racers use the LOWEST octane they are able to use.

Please using your tactics give us a link to this giant BS theory. This is totally off the wall even for you.

HUUMMM do you think sanctioning bodies limit how low racers can go with their octane

Dam now I'm going to have to go looking around for the good 80 octane bootleg stuff the next time I go to the track and ignore the 105 as it's no good................. But gee maybe you can explain why all the winners are still using the highest octane they can get.

The only difference in racing and street fuel is the octane ....no really.

No really you need to back away from the keyboard if this BS is the best you can come up with

 

I can't believe these types of conversation still keep coming up on here. Kind of why I have pretty much stopped being active on this forum.

Anyways, my ECU was flashed by JsRacing the fuel & ignition tables were altered and a slight change to the VTEC activation point (just 100rpm lower), but with the change, the ECU requires HIOC (99RON) or around 95~96 R+M/2 standard stateside. Without it the engine would ping and retard itself to where it called itself Simple Jack. I don't baby my Fit around, it gets raced (well when the tranny isn't busted up) so I know the majority here don't use their Fit in this manner and what they consider getting into the Fit would be getting on the freeway entrance. If that is all you are doing and not flogging your Fit like it enjoys then stick with regular fuel. If you are one that likes beating on your car (in the appropriate setting) go ahead and use a higher octane because the ECU does indeed alter timing within the engine based on what you feed it.

 

It is amazing how much BS is floating around on this topic. The last time this topic was up I asked for specifics. The "Know it alls" could not answer the specific questions posed. So two of them responded with profanity while trying to explain their vast depth of knowledge. It was obvious that their limited scientific knowledge and vocabulary prevented them from even explaining their own erroneous thoughts clearly.

I suggest that if you want to learn more on this subject that you go elsewhere to find the answers.

Find out what octane numbers mean and when higher octane fuel numbers are necessary and used.

Look up the BTUs per gallon of various fuels you are interested in (winter, summer, E10, etc.)

Also look up the abbreviations GGE and AKI and their application to the various fuels you are interested in.

75% of the stuff you read here is BS. So go figure it out for yourself if you are really interested.

Hint. Octane and energy (BTU's per gallon) are not necessarily inter-related.

Good Luck.

This forum is excellent on many Honda Fit related topics and I've learned a lot from many people here on many Honda Fit items. My thanks to the many who have lead the way and proven or dis-proven many subjects that I know little about.

 

This is correct. To much octane is like banging your head against a wall.