c5kirk

I know that the new Accord is designed to run on regular but was just wondering if there is any benefit (hp, mpg, etc...) from putting in premium or if it would just be a waste of money.

Thanks!
Kirk

98CoupeV6

Depends. I don't think there is any advantage in the K24, but the J30A2 gains about 10 horsepower using premium fuel (quoth a Honda engineer). This hasn't been proving on a dyno, but I would tend to believe the Honda engineer. Somehow the ECU advances timing slightly when you use higher grade gas.

In most cars, there is no advantage. The J30A1 in the 98-02 Accord V6 actually lost some power.

proteus

its the J30A4 in the 03 and the engine has knock sensors which detect knock and like said above the timing is advanced. If you have the v6 you should experiment and see if you can tell the difference.

Level_7

There's no way using premium fuel would increase HP figures at all - much less by 10HP! If however, you have a high compression engine that requires high octane gasoline, using a lower grade will result in _less_ power since timing will be retarded.

98CoupeV6

It's comforting knowing that our members know more than Honda engineers

proteus: thanks for the corrections.

Level_7

I never said I know more than Honda Engineers (on that particular point), so this is what you're going to do: give me the name and position of the person who said that, or the website/publication/newssource you found the information on. Until you do that, I refuse to believe such a ridiculous claim.

Do you know what octane ratings mean...or the chemical processes that occur during combustion? There's a difference between blindly/stupidly believing whatever you read, and being educated about the matter at hand.

98CoupeV6

And then there's thinking you know everything.

Charlie Baker said it, as did Yasuaki Aasaki. "The Nissan Altima, which takes premium fuel for its V6, has been selling like crazy, based largely on its hot acceleration, and Baker says the Accord can just about match it. However, he adds with a smile, if you run premium fuel in your Accord you'll get more horsepower, and he's willing to bet it will be an Altima killer"

http://www.nctd.com/review-drive.cfm?ReviewID=1210

"although Accord's will jump 10 horsepower or so on premium, V-6's chief engineer says"

"The Accord V-6 ratings assume regular-grade fuel, and Honda will market it as a regular-fuel engine. But — pssst — it's good for another 10 hp and 10-plus lbs.-ft. on premium, acknowledges V-6 engineer Asaki."

http://www.usatoday.com/money/autos/...1-accord_x.htm

But of course the lead designer for the 2003 Accord and the lead J30A4 engine designer don't know what they're talking about compared to some kid on the internet Perhaps next time they put together they car he should consult you.
And yes, I know quite a bit about those processes. And I know how the Accord's ECU can adjust timing slightly. I'm majoring in mechanical engineering at SUNY Binghamton.

wned:

Level_7

This is what I said earlier, in the begining. Just because its being marketed as a regular grade machine doesn't mean that it was designed for that in mind (that's why the timing is retarded - it get's advanced when you use the 'correct' grade of fuel). My GS-R doesn't require premium, so it could have been marketed as a regular grade machine - and will happily run on 87 or 89 octane, but with a power loss. So, in the end, that's all it is: "The GS-R only needs regular grade fuel, but psst - use premium and its good for another X HP". (And if its ratings assumed regular fuel, then that X increase would show up on paper). That statement is true, but the engine didn't actually gain anything by using the fuel it was _designed for_ - it just lost horsepower buy using the fuel it was _marketed for_. Do you understand this reality?

Oh, and I'm not 'some kid on the internet'...since you didn't post your age or anything else, and since you use very intelligent argumentative structures like wned: , many questions remain.

98CoupeV6

Shutup man. You were wrong. Obviously the car was designed for 91, as using 91 in my car would result in slightly decreased horsepower.

My age is in my profile. I'm 2 months older than you. My cousin's birthday is the same day as yours. Sorry I didn't have to go through an elabrorate BS process of attempting to save face like you did to prove my intelligence to you

As I said originally, J30A4 gains (don't be an ass, that's what it does in comparison to using 87 octane) about 10 horsepower using premium fuel. I even backed it up with facts. Stop arguing, thanks.

Level_7

Why are you finding this argument difficult to follow? My _very first_ post stated correctly that the engine doesn't gain anything by using a higher grade fuel...it just loses power by using a lower grade fuel - which it was not designed for. Just like my car would lose power if I didn't use 91octane - when I switched back to 91, would you say my car gained power? No.

That engine is a high compression engine designed for high octane...no one can argue with that. Therefore using lower octane gas causes a power decrease. If you still do not understand, then PM me for extra help. Thanks.