In the city? Yes it does. On Highway it does not. As least it didn't for me.

That's all fine and dandy that you "know a lot about engines and basic performance" and to be honest I don't care how many fit's you've owned in the past 3 years. Octane does not equal HP no matter what car you drive.

And I did run premium in my Fit for shiggles. Made no difference what so ever.

 

sure, you pay for the dyno I'll supply my 2012 fit sport, i have already seen the results on other vehicles.

 

Yeah... let's not. There's enough threads here about premium vs. regular... Besides gas is not a bolt-on choice (on topic)...
Though I have to admit I'm very curious about 11 Fits in 3 yrs....

 

Eh, if canuck901's claims have any merit (which I do not believe they do), then fuel choice COULD be considered a "bolt on". It's not a change to the vehicle, but it's something that can be added to everyday operation that would result in increased power.

Of course, octane is simply a measure of a fuel's resistance to detonation. canuck901's claim that V-Power contains no ethanol is the only thing that MIGHT give it some credence, though I can't find anything on Shell's site confirming that claim (I do not use Shell fuel myself.)

Cars like the Hyundai Genesis, which are designed to run on higher octane fuel, have ECUs that are programmed to adjust for lower octane if used. You can put 87 octane in a Genesis and lose power, most likely due to an enriched mixture and retarded ignition timing. In that case, octane matters. In the case of our cars, which are designed to provide all 117 hp with 87 octane, no more power is to be had from anything "better". The ECU is not going to lean out the mixture and advance ignition timing if you put higher octane fuel in the tank.

I'm just a noob, though. I don't really know what I'm talking about.

Do you have any of those results available to share? On cars that are designed to be run on 87 octane, that is. What I'm saying isn't limited just to the Fit, although with our small, relatively low-output engines, any gains would certainly be much smaller than on larger, more powerful engines.

 

I import fit sports from the US to Canada, sell them

 

I have driven 36 and 40 horsepower VWs and 60 horsepower VW pickups with the bed loaded down with newspapers or sheet rock and was able to get where I was going... Hootie mentioned momentum and strategy... It would take me forever to regain the speed I had loss by having to use my brakes and pulling out to pass on a 2 lane road was impossible if I was to just pull out without having gained enough speed in advance of doing so in those really slow little cars... I stay way back from the car in front of me that I want to pass and keep my open for an opportunity to downshift a gear or two, accelerate before pulling out and do so soon enough that the person in front isn't going have a chance to speed up and close the door on me... By downshifting instead of braking when the traffic in front is slowing will extend brake life and put your engine revs higher where there is more power and torque too use if you need to slip into another lane... Don't be aggressive but at the same time don't hesitate to execute your maneuver... I don't think that many people are able to focus on what is going on around them or are too easily distracted by all of the gizmos and gadgets inside their cars to be driving in traffic...

 

I eat a lot of cheeseburgers. I don't claim to be a beef expert.

I'm not calling you a liar, canuck901... just asking for something more than your word to back up your claims. Too much misinformation gets spread around internet forums as a result of someone saying something with absolute certainty, and never providing any hard evidence to back it up. Anything that's "too good to be true" spreads like wildfire, because everyone wants easy, affordable gains.

 

It astounds me that Honda and other manufacturers have been able to create an engine management system that will allow an engine with a compression ratio of 10.4:1 to run on fuel with an octane rating as low as 87... It's just as neat that it is capable of adjusting the air/fuel ratio and ignition timing to run even better and cleaner with higher octane fuel.... 87 octane isn't recommended but is stated to be the lowest octane rated fuel you can use... It's cool that you can chose to use it if you'd like to... I wonder if anyone using premium fuel has had to clean their EGR ports?

 

I've been running 87 octane since I bought my car in September 08. Over 250,000 miles, and I've never needed to clean my EGR ports. Never once had a CEL. Still getting 36-42mpg, driven hard.

I'm curious to see how the manual is worded now...
Just checked my manual. It simply says that the Fit is designed to run on 87 octane or higher, and then goes on about fuels with quality detergents, and what fuels to avoid (anything with MMT or methanol... up to 15% ethanol is acceptable, which is interesting.) I don't feel that it is suggesting any increased performance from anything higher than 87 octane. Perhaps it's worded differently in newer editions? My Fit is one of the very first GEs sold in my area.

 

Knowing not knowing is a good thing... Not knowing not knowing can be dangerous...

Good! Glad it's not a case of good driver/bad car or bad driver/good car.

 

A wise man once told me, "it's not until you admit that you know nothing that you can truly begin to learn anything."

That being said, I HAVE been around for a while... I don't claim to know more than I really do, but I can't honestly claim that I know nothing, either!

 

You've got a lot more miles on yours than I have on mine for sure... Mine's a GD3 that will be 6 years old in a couple of months... It is low on miles but has had a lot of fuel/air mixture run through it with help from a KWSC at 10psi boost so of course I must use at least 91 octane... There are a few of us that have been around long enough to have developed very sensitive butt dynos and can actually feel a difference... I can accept that some people won't be able to feel a difference in performance but since my car is only driven to medical appointments and for pleasure drives on scenic back roads with lots of hills and curves I plan on continuing adding home brewed octane booster to the highest octane fuel I can put in it and looking at the resulting increase in ignition timing advance and whoever is trying to stay up with me in my rear view mirror..

 

With a supercharger, your setup is a good deal different, though. Clearly, octane matters in your case! Your engine is no longer "made for 87 octane", and changes in octane with forced induction have a greater impact.

What engine management are you running?

I've never looked into such extensive mods, as my car is my work beater (and I certainly beat on it! :lol: ) I'm really not all that knowledgeable about doing such things to anything so new (most of my performance knowledge comes from tuning OBD1 F22A and H22A engines)

 

An intake will give you the noise you want, but will strip low end power for high end gains.

 

Yay, another reg vs premium gas debate.

I won't bother with attempting to change anyone's mind. Just voicing my experience.

'97 Mitsubishi Mirage, that was a car I owned a good while. My dad actually bought it in 2001, not used, but rebuilt from a local body shop. In the seven years I drove that thing... regular gas would always make it feel sluggish during acceleration. Pumping premium would give it a little bit more life. I could swear I could feel when some else borrowed my car long enough to pump gas, since they would pump regular. But the reality is, the engine was probably at the stage where it needed a major tune up to clear up any knocking being caused by regular gas.

Fast forward to 2010 Honda Fit. I used regular for a year with the occasional premium being pumped once in a while. There is no data to justify the premium gas... my MPG change, if any was well within the margin of error, especially since my MPG changes quite significantly based on my mood. And while some of you folks want to argue any "butt dyno" effect is merely placebo... it's enough that I now, only pump premium.

I wonder if the "opposite placebo" effect exists... where you think something is merely a placebo effect, but is actually happening.

Meh, whatever.

 

The PRM intake I added gave me more high end power. Didnt help any on the low end. I also have an axle back greddy exhaust on my car. Did not really notice any difference. I mainly put these on for sound. Unless you do alot of bolt ons to these cars, your not really going to feel it.

 

Bolting on a super charger or turbo if done correctly seem not to take much of the life away from the FiT's little engine but can make a huge difference in power.
Tex has a S/C on his GD3 and Chris @ DSM is the turbo-go-to-guruman here.
Both carry a steep price, but the need 4 speed is always $$ =
These keep the weight ratios close to OEM, not sacrificing handling or suspension.
Enjoy your Fit! it's still and eco/econo box and fast will take away what it was made for MPG.
Welcome to FF's!

 

It is surely different now but before doing boost my scan gauge and the word from a number of freaks with them had witnessed the increase in ignition timing and ability to go up hills at the same or higher speed with a lower % of throttle... I went in full tilt with the KraftWerks after using just the 5psi base kit.. The High Boost 10psi kit required me to pull out the ECU and send it to Hondata for a reflash...I presently have the car on jack stands to do more changes that includes an A/F ratio meter, AEM F/IC, and Cooling Mist water/methanol injection. Also Weapon R intake manifold and competition header.... I'm laughing at how foolish an old man I am by putting more into parts for this little shitbox than I am seeing very nice 2nd hand Range Rovers going for... It's a ball to drive, the young gear freaks that meet on a parking lot in town are on their phones calling other guys to come look at my car when ever I stop to talk to the ones I know... Most guys my age are into Harleys or metric clones.. I did that 25 years ago along with many other bikes and cars... It's kind of nice being referred to as an eccentric old guy instead of that crazy mofo..

 

Haha, yeah I know the feeling! I don't really plan on modifying my Fit (my mileage is my greatest modification!), but my weapon of choice is a 92 Accord (H22 swap with minor bolt-ons and a street tune... a work in progress yet.) I'm 32, driving a modified 20 year old car that is frequently overlooked by tuners.
The key is to have something you enjoy driving. As long as you have that, that's all that matters!

I bet you could probably see even more power, and possibly greater fuel efficiency, if you had the ECU custom-tuned on a dyno for your specific application. A generic reflash, even from a reputable source like Hondata, can't be quite as good.
Still, I bet at 10psi, that thing hauls! I bet you could keep up with my Accord pretty easily, if not beat me.



To keep this at least somewhat on track... how much did the base SC kit cost you? Not just the price of the kit, but all the additional parts necessary to make it work? The OP might benefit from just going that route, as small N/A bolt-on mods don't give much power, and the overall cost when you add it all up can be surprising. One big mod, like a supercharger, even at 5psi, will be a better power increase than any number of bolt-ons.
I just hope the L15A's internals are stronger than the guts of an F or H engine... people boost those things and break ringlands left and right. Then again, those are 150k+ mile engines that are 20 years old!

 

You crack me up TC! I like crazy mofo better...