More on Gasoline
 

Wouldn't it be nice if gasoline was gasoline and not part corn? Well, I guess it's good for the farmers.

Don't use E85 in your Honda.
https://engines.honda.com/support-an...tions#fueltype

Both Honda service and a good, local mechanic recommend using non-ethanol occasionally.
Non-ethanol stations -
https://www.pure-gas.org/

With direct injection, no fuel passes through the intake port and over the valve, which would help to clean and cool the valve. This is the prime reason for problems with direct injection engines. I paid our local dealer $300 for an oil change and a fuel system cleaning, and it made no difference. The Check Engine light came back on. If the car hadn't been totaled, the next step would have been to pay $1,000 or more for new injectors. We had already paid $700 to get the Check Engine problem solved, but the warning light kept coming back on. Both the dealer and the mechanic said the problem was related to direct injection - and also by a bad choice of injectors for the 2015 and 2016 Fits. There wasn't a recall because not enough people complained.

Pure Gas is a fantastic app that includes maps to good gas. Great share!

If someone pulls up to an E85 or E30, they better know what they are doing... Are you writing this because you have seen Fit owners buying this stuff? A fuel that the car is not even designed for, being put into the car, is simply negligence. Sorry, I am a little bold on this one because I cannot believe how many hundreds of people I have met that don't understand gas pumps.

All gasoline sold in the USA can have up to 10% ethanol without them making it very obvious on the pump. Gas stations that sell ethanol free, which are rare, often have to brag about it because of the increased price.

EDIT: All cars produced for use in the USA after 2001 and beyond are supposed to be able to accept E15, but the pump serving E15 must be labeled. (E10 pumps will not be obvious) https://www.fueleconomy.gov/feg/ethanol.shtml

No - just because of the recent posts about gasoline.

If I were a mod, I would UN-sticky that thread, about what octane gas people are using

The car was intended for 87, everyone should just run 87 (imo), and not even entertain a discussion .... let alone a sticky thread to encourage more folk into trying higher octane




(note, I am a hypocrite because I am currently testing 91 on my car. but at the very least, my ktune does call for it)

Yeah, I used to think that too, until the wording in the Honda manual was pointed out to me. The Fit will actually run any grade of fuel from regular to premium. Honda does not reccommend any specific grade. The engine will adjust to whatever grade you put into the tank. Honda merely states that it has to have a minimum octane of 87 which most regular gas has. You can run premium all the time if you want, you should get slightly better gas mileage but probably not enough to justify the higher cost.

"FUEL RECOMMENDATION - Unleaded gasoline, pump octane number 87 or higher."

Most people have made up their minds without looking at the facts. Their opinions become facts. I have been driving for 54 years, and I use the cheapest premium, not :"top tier" gas stations for my BMW (sold) and Porsche 911 Turbo since they were new. Now, the Turbo has a MSRP of $145K. My Honda Fit gets 87 octane at the lowest priced stations. You guys are putting premium in your Honda Fit? I can understand you want to take care of your car. But, putting premium gas or only use "top tier" gas is only wasting your money. Top tier gas is used for emission tests because someone is getting paid. I continue to advocate I can get 500 miles in a tank of cheap gas. Can you?

fixed that for ya

you're correct for about 99% of the population that waste money on higher octane. I do advocate, everyone uses 87 octane, unless tuned for something else. IMO ... the power diff is worth it, TO ME.

you make good points about top tier, I'm just one of the lucky few that have cheaper top tier in the area .... so purposely going out of my way to NOT buy top tier, would result in paying more. YMMV

You need to understand gasoline. Repeat after me ..Gasoline is gasoline. Whether it is 87 or 93 octane, it is just gasoline, same amount of energy regardless of whether it is 87 or 93 octane. The only difference is the temperature at which it will ignite. If you have a high compression engine that compresses the volume of gas to a smaller volume, you do not want the gas to ignite too soon because it is hotter when it is compressed to a smaller volume, which causes knock. The Honda is a relative low compression, Using high octane gas does not give you more power. You are just igniting high octane gas at a lower compression volume, ie, lower temperature. No help. High compression engine ignite at a higher temperature. From thermodynamics, the higher the temperature difference between ignition temperature and exhaust gives more power. This is why higher compression engines is more powerful, unless you are talking turbocharged (lower compression) engines, which is a different story.

If you don't believe me, try another person...
Unless your engine is knocking, buying higher octane gasoline is a waste of money. ... In fact, in most cases, using a higher octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage, or run cleaner.

huge favor Wasserball. I'd like you to visit the following 2 threads, and post the following / repeat after me:


https://www.fitfreak.net/forums/3rd-...eck-sheet.html
"CarbonTek, gasoline is gasoline. Please re tune using 87 octane and post your results"

https://www.fitfreak.net/forums/3rd-...ml#post1404291
"KTuner, gasoline is gasoline. Please re tune using 87 octane and post your results"

Yes All gasoline has the same amount of available energy per gallon assuming a generally standard source.
In the engine ,, Octane is the combination of base ignition temperature + the SPEED and temperature that it burns at.
In really hot weather, running higher octane helps keep head temps down. (That's good.)
Your engines ability to exploit the octane is directly related to the level of tune.

If you go way back and read the implementation plan for standard fuel, IIRC they are supposed to be raising it to 15% then 20%,
Don't know if that got cancelled it was an Obama thing...

The fit should handle low octane easily from a physical perspective, the enigine design is just like a LS Corvette,
reverse flow and has full cooling around the cylinders.

There are two different types of people.. Those who believe octane make a difference, and those who do not.

There are two different types of ECM calibrations... One that has a predetermined max timing advance no matter what the fuel potential is, and the other is calibrations that seek to exploit as much power from fuel as they can. And the sneaky third type, ECM's with manually adjustable distributors...

If I consider the fit engine is about 25% the size of most engines that people love taking to the dyno and testing this sort of thing. I'll summarize the essay I could write by saying the power gain is likely to be a max 2hp at max hp rpm. So around town, maybe a 1/4 - 1/2hp at regular driving rpm's. And 2hp is probably less than the difference between proper tire inflation, or cold transmission, or a hot sunny day with 90 degree roads.

Sorry, I am not trying to enter the fuel debate. I likely need to go find one of these threads and get my popcorn.

Good top tier articles -

https://www.consumerreports.org/car-...h-extra-price/
https://clark.com/cars/top-tier-gas-...an-engine-aaa/
https://www.carfax.com/blog/top-tier...edicine-engine

The cheapest gasoline in my area is from Citgo stations - top tier.

Thank you. I'll pay the extra 30 cents per tank.

Those are two different things however.
I just recuse myself of entering the Premium vs. Regular debate. Only saying that like I think nearly everyone, I've experimented with running higher octane gasoline with my Fit, and for me? I don't notice any difference in performance or MPG, so I just fill with regular. But I don't argue with people who want to use a higher octane and/or feel they are getting benefit. Maybe they are? My vehicle is new enough still...that it runs perfectly fine of regular.

But as far as "Top Tier"?
Well where I live, it's actually pretty hard to find stations that DON'T sell "Top Tier" gasoline. Almost all major stations, now adhere to those standards.
I'd almost have to be passing through Mayberry, to find a station that isn't a Top Tier seller. If Goober Pyle is the attendant? You've arrived.

For me? My vehicle is one of the biggest investments I own. That being the truth, why should I seek out the cheapest of anything for it? The difference in price per gallon at for example a Chevron station (Top Tier) vs. Jacks Gas-And-Go (???) is absolutely minimal to the point of being nearly non-existent.

I think Top Tier as a designation is much more just two things. One...yes a marketing tool. "Buy Top Tier Gasoline" is something sellers can advance as a distinction. Although it is so common now, it's hardly even mentioned.
And Secondly, it is a set of standards applied to the detergent and additive packages within the gasoline.

Since IMO....I'm not really paying any premium, or a very, very minimal one for that distinction? I have no problem with Top Tier gasoline or Top Tier retailers.

Excuse me if I sound uninformed, Top-Tier and High Octane gas are two separate things, correct?

I usually buy from the Shell down the street from me but I usually put in 87. Sometimes I have to go to the Sheetz in the town that I work in to get gas. That doesn't seem to be in the Top Tier AAA list. The other gas station I hit in my work town is probably not on the list either.

Yep....
 

That's what I'm saying above.
As far as I know all stations offer a "Regular" "Mid-Grade" and "Premium" grade gasoline that increases octane at every step. BUT...
Not every station offers "Top Tier" gasoline.
Top Tier is a definitive standard in regards to additives and detergents in the gas...not the same thing as octane.

Except it does. On a little L15 you get maybe 1-2hp. Forced induction and larger HP engines the increase is greater. I never used it in my Fit.

Did you remove the heads off of the BMW and Porsche and check the valves? How many miles are on the engines? I am not saying it makes a huge difference but there are tests that show TT gas cleans the engine. If I can clean my engine and help my piston rings, valve seals and other internals for pennies on the dollar then I am going to do it.

Honda put a DI engine in the Pilot a while back and it does not seem to have a carbon issue for from what I could find. Also on a side note VW/Audi recommend running an engine above 2k for 12-min to burn off carbon and other engine deposits. Well someone with a 3 mile city commute would have more of problem with carbon then a highway commuter. So maybe these issues are more environmental then design.

One red line a day keeps the carbon away :)

So I in my spare time am a track rat, I work on just about anything with a motor,, I've spent hours working with Engineers from multiple fuel companies.

I've tuned rotary engines. Best power is with lowest possible octane if its NA The old Imsa engines use 68 octane (Basically coleman lantern fuel)
A properly running NA rotary cannot ping, it only has about 7:1 static compression, it builds dynamic compression as the RPM climbs.

I've run a 1.5 that makes 250 HP normally aspirated,, running on straight methanol, Hillborn injection and 14.7:1 compression. (At 10,000 rpm...)
You could ,, if you had the right software tune some decent power out of a fit with 100% 114 race gas, but the car would not run on well on Pump 87 any more, most ECU's can't handle a spread that wide.

I've also seen small block chevy engines running pump 87 make 800 HP, with a Electromotive ECu and some serious mad skills on the engine builder and tuners side.. (Dont try this at home kids... LOL)

My 07 FIt shows a nice drop in head temps when I run 92 (Premium is a marketing term BTW has NOTHING to do with quality. )
Which is nice driving on hot weather for engine life..

As far as power running different octanes,, in a fit.. Show me the dyno slip and the 1/4 mile time.. Without data its just bench racing butt dyno gossip. :vtec:

Now if your talking RACE vs PUMP gas ,, there is a solid difference in power available between 92 Pump and 92 Race Spec fuel,
Race gas doesn't have VOC limiters in it, so the fuel evaporates/atomizes way better than pump, that's where the
power in most stock ish engines comes from when folks mix race with pump at their local drag strip... The octane is just a side benifit..
Dump a tablespoon of pump gas on the sidewalk on a hat day and a tablespoon of say
VP 92 spec. The VP is gone in a second the pump stuff takes a while. Carbed engines are especially responsive to it.

Nice post.

Would running higher octane fuel and changing the ECU program create more power if nothing else changed?

If the ECU advances timing and adjusts for the higher octane wouldn't that increase HP? It would probably not be measurable in a Fit but still an increase I would think? Worth the extra price, not to me!