89 or 91 Octane Questions
 

Does anyone use these in their Fit? If so have you noticed any "improvement" in the Fit's performance? Thanks.

Best,

Dave

I always run 89 with 10% ethanol in my gd3 AT. It runs fine.

Once, I ran 91 in it and the car seemed to run quieter, but performance and MPG were not effected. IMO 91 is not worth the price unless your car requires it.

Nope. Around here those are ethanol blends. The 89 costs less but fuel economy suffers. Don't need the octane.

Cheers

IMO its all the same to me. I use 89 with my car and every few tanks I put in a bottle of the fuel injector cleaner with a refill to clean out all the gunk.

The owners manual says it's designed to operate on unleaded 87 or higher. 87 has worked fine for me so i'll stick with that.

i only run 93 and i have in all my vehicles since ive been driving. i ran 89 once in my mothers 2003 sonoma and it coughed like you would if someone blew smoke in your face. but she has been running 93 in that truck since we got it. in some honda owners manuals it says to only run 93 and 89 only in emergency situations.

The only Honda's which designate to run only 91+ are the ones that have high compression aka older Vtec engines and certain i-Vtec models.

The fact is that the car cannot and does not make use of the higher octane, unless you install a supercharger or turbocharger. No exhaust, no intake, no air cleaner, no spark plug change, will make any difference in that fact. I follow the owner's manual (see below) and run 87 octane without incident.

I am much more concerned with the quality of the fuels I put in my Fit than I am with the octane, and so I only buy quality gasoline from reputable stations. Spend your money on quality 87 instead of buying crap 89 or 91 and your car will love you for it.

http://ims.hspn.com/pic.php?u=3MKM9S&i=6028

I get to talk with Yamaha engineers once in a while as I evaluate some of their snowmobile prototype items and midwest hqtrs is only 4 miles form me.
Higher octane actually burns slower.
On their 4 cylinder 1000cc 160HP snomobile engine (which is a very slighty detuned R-1 motorcycle engine)
They say you will get less performance, less MPG and more carbon build-up if you run higher than 87 octane.
So I'd say use the faster burning lower octane unless you are getting some sort of knock or ping.

Car has been a little more quieter once I put a tank of 91 in it. First 2 tanks were 87

Yep, that's what octane does; it delays the onset of combustion. Higher compression engines need it, lower compression engines do not.
Sounds good to me! :)

i used all 3 grades of fuel. 87, 89 and 91. i felt no difference, no smoother accel, nada. my .02

Never use high octane gas unless your vehicle owner's manual tells you to.

for an economy car such as the fit, 87 is good enough. no matter how high of octane u put into a fit, its not like it will suddenly have nsx power...the economy is bad so might as well just save money on gas or save up for a real performance upgrade such as an engine swap or turbo kit.

That's exactly my understanding of this too.

I always run 87, I bought this car to save money, not expecting it to kill in a street race, although Im pretty happy with its pep. its no barn burner, but it gets to speed well enough for freeway merges and passing.

I guess many here don't understand the fact...filling with a higher octane MAY decrease power and fuel economy.

What I came in to post: Octane, in practice, is effectively the resistance to compression-based combustion. Unless you need it (High compression engine or forced induction), the lowest octane your engine can run safely, the better. I filled up with 91 on accident once (Used to have a GS-R), and I noticed the Fit was actually harder to start in the mornings.

Exactly!!!
If I wanted to "fly" and pay for premium every time I filled up I would have kept my CL-S. :vtec:

If people buy the fit to go fast...they need their head examined. :hyper:

I have a lead foot..the fit actually helps me control my lead foot.
No temptation there...ha ha. :cool:

Lead foot in the CL-S = 120+ mpg highway (20 mpg)
Lead foot in the fit = 70 mph highway (37 mpg)

stick to the 87 people.

Just put in a tank of 93 octane and try to drive it over the Rockies. No power at all.