kc-runner

Hi everyone, settle this one for me. My girlfriend thinks it is better for her stock 2004 VTEC Accord to run 89 and sometimes 91 octane gas. I tell her it is a waste of money to do so. I have told her that if she wants to do something to prolong engine life spend her money on regular 87 octane and once a month put a good injector cleaner such as TECHRON or SEAFOAM in the tank to keep the injectors and combustion chambers clean. Give me your thoughts.

briq4

manual says to use 87. I had a 93 accord which actually said a minimum of 86 was acceptable. Not that you can find that anywhere in new jersey, but it was OK to use. I drove that car from 35,000 miles to 365,000 miles. Figure at a constant price, say 2.00 for regular 2.10 for mid and 2.20 for premium, lets say I got around 29 MPG or so in that car. Over the life of the car I used 11,379 gallons of fuel. If prices were as low as my example regular would have cost 22,758.00 Mid would be 23,895.90 and premium would have been 25,033.80.

So $2,275.00 is what I saved by using regular over premium, which over the 12 years came out to 189.58 a year savings. Personally I like the idea of having the 2.275 dollars in my pocket, oh and as far as using gas additives or anything like that, I never wasted my money on those either. Now I did wind up with clogged EGR ports at about 240,000 miles, but I think that would have happened using premium as well, carbon is just a byproduct of buring fuel regardless of the grade. And even that job wasn't anywhere near 2,275.00 to repair.

If it makes your girl feel better to waste money tell her feel free, but I personally don't see any reason to waste it. Just my .02 take it or leave it.

OH and I have an 05 civic with vtec and am using regular as well, up to 72,000 miles on that with no issues either.

And my mom has an 04 Accord EX V-6 and also uses regular and she's at 134,000 miles now.

I just can't see wasting money like that.

GoLowDrew

You will get 1000 opinions. I have a friend that swear by Shell 89. Not Chevron. Not BP. Shell.

Back in the old days, I could tell the difference - like my 88 Civic. Before I sold the car, a tank of 91 just made it smoother.

Today, with modern electronics it can adjust.

I have even put 87 in my car that recommends Premium. Never noticed any difference. I did this for 1/2 of time I own it.

You money. You car. Do you what you like. Your GF, I mean.

baller862

If you are using 91 octane on a stock honda then your the worlds biggest idiot/

0Janet@bisimoto

You answered your own question.

BLKFLSH

I've only used 87 in my 03 V6, and it still runs as smooth as day one at 67k miles. I see no need to spend more. Isn't gas high enough. I do use "top tier" gas (Texaco) for the detergent additives, so I don't need to use fuel system cleaners, such as Techron etc.

George Knighton

I'm not sure what you mean when you say VTEC Accord, since the J Motor V6 is VTEC and the K Motor K24 is i-VTEC of a sort.

If all she is after is the health and long life of the motor, then there is no reason to use anything other than 87 octane (American pump octane).

However, there continues to be anecdotal evidence that the long term use of high octane on the J Motor will allow the computer to gradually make improvements to the way that the car runs, and people at other sites have published dyno figures of their stock V6 Accords that appear to have gained as much as 15 HP simply from the use of high octane fuel.

After running 93 octane on my own 2006 Accord, I put it on a Dynojet.

All I can say is that Honda would have got away with rating that particular motor at 260 SAE Net HP or more, instead of the published 244 HP. The Dynojet figures were amazingly close to the published figures, and nobody could believe that I had not made any improvements to the motor at all.

If you want to do this, it is completely safe.

However, you have to do this continuously, tank after tank after tank. You are stuck with using high octane gasoline if you want to avail yourself of the complete capacity of the electronic device's ability to gradually improve the car's performance.

This same motor gets 30 miles per gallon or more, very often. It's simply amazing. Since the car comes on the cam at 5,000 RPM and the secondary opens at 4,000 RPM, you can move remarkably quickly and still get very good fas mileage as long as you remember to shift below 4,000!

These are great cars with great motors, IMHO.

Be forewarned, however: You're stuck with using high octane if you want to do this. A single even partial fill with 87 octane will cause the motor to notice a knock, and this will cause the computer to immediately fall back to the default tuning.

A single even partial fill with 87 octane will cause you to have to start this long 3-month process all over again.

88Hatchy

ignorance/

boxeocampeon

use 91 its recommended by most places

YeuEmMaiMai

that's only true for pre 03 accords that cannot adjust engine timing based on fuel

03+ accord have the ability to run on higher octane fuel for more power. trade off more cost for more hp

Cripton805

My timing was somewhat low on a 90 Integra and I switched to 91 Octane and it seems to ride smoother and it picked up the timing a little bit. I also feel a bit more power and the gas lasts longer.

checkZvtec

i noticced no performance gain from 2 93oct fill ups and a decrease in my total miles per tank. i usually get around 400 miles per tank, i only got 370 miles before each fill up with the light on. i never wait for the light besides those 2 fill ups to see how far she'd go. so, i switched back to 87. i have heard it runs cooler than 93, thereby increasing overall efficiency since less heat is being made. iono what to believe but my gas mileage...

87UNITS

actually its how you drive matters... higher octane will give you a higher gas milage.. if you dont ever punch it.. its like Manual transmition... they say it gives you better milage... but its just how you drive it... because i bet i can get better milage with an Automatic...

the fuel burns better, thats why it would need less to reach a certin distance, but it also burns better... thats why it give you a little power boost... you decide what you want..

20accord06

I used 93 and i feel that it drives better and motor isnt as loud at idle.