[FLNusselt]

I'm new to this Forum since I recently bought a 2006 Accord Coupe V6/6M even thought I used to have a Full Blown Turbo D16Z6 Civic Coupe EX that I sold about 4 years ago.

To the point, I became very curious about the performance of my car with regular or premium gas and checked out this forum and found two groups.
1-Those who believe on the statement that premium gas yield more power on cars that HAVE A KNOCK SENSOR like ours.
2-Those that think that it is sort of a fantasy or a placebo effect (Haters of the premium gas statement)

Interestingly I found some information regarding the claims of an Honda technician(That I believe is a Round Up/Proficient Engineer) named Asaki Yasuaki that premium gas yield an additional 10 HP. Some said that this guy was full of it and it was BS. Based on that, I took my time and went out for more factual data on this topic and found out that this guy Yasuaki Asaki, have a Patent on his name US 6947828B2 assigned to Honda Motor Co. LTD titled "Knock Control System for Internal Combustion Engines". I think this guy knows what he is talking about when he said that premium gas will free up some power on our engines.

The Patent information can be accessed with this link "http://www.wikipatents.com/US-Patent-6947828/knock-control-system-for-internal-combustion-engine/Page-21". More interesting, if you read paragraph #5 on page 21 it clearly explain the adjustment done by the ECU to the ignition timing based on the knock sensor signal. On a 10.0:1 compression ratio engine that is conservatively tuned for 87 Octane, a timing advance with higher octane gas will definitively yield additional power.

Food for thought...

 

[Versatile337]

pretty cool stuff, now post a youtube video of you dynoing your car with 87 octane vs 93 octane and school everyone

 

[Yal]

pretty cool stuff, now post a youtube video of you dynoing your car with 87 octane vs 93 octane and school everyone

Nice :thmsup:

 

[A&Fbro28]

Sp[ort compact did a dyno of 7th gens or either vtec.net and on the j30 they gained 10hp swithching to 93 octane so Honda even started telling customers this back when they were sold. Ill search hard for where it was. there were dyno graghs too.

 

[AMAN1]

^ I thought someone did dyno runs on their 7th gen and found premium brought negligible gains.

I think you won't see any noticeable gains on the stock tune, but since this engine has a relatively high compression ratio, you'd probably see significant gains using 91 over 87 ONLY IF you did a proper tune.

 

[A&Fbro28]

^ I thought someone did dyno runs on their 7th gen and found premium brought negligible gains.

I think you won't see any noticeable gains on the stock tune, but since this engine has a relatively high compression ratio, you'd probably see significant gains using 91 over 87 ONLY IF you did a proper tune.

Per vtec.ne comparing cl-s6 dyno. With premium in the 03 accord it put down the same power as CL-S. This wont happen on 08 automatics as they arent true vtec. The 08+ 6spd should gain power from using 91+ octane.

"The Accord went second and performed like we thought it would after hammering the throttle for a couple of days. No shy, retiring commuter engine, the J30A4 is a beast. It belted out 217 hp and 195 lbs-ft of torque at the wheels. And this engine is only rated at 240 hp/212 lbs-ft at the flywheel! Of course, we did use premium gas to extract the most possible power and the J30A4 rewarded us with a surplus. By comparison, last year's CL-S 6-spd pumped out 218 hp and 201 lbs-ft (also on a Dynojet) from its J32A2 engine. We felt that the J32A2 was pretty accurately rated at 260 hp/232 lbs-ft at the flywheel. If this is the case, that would make the Accord a 260 hp/225-230 lbs-ft engine. Not bad for 3 liters, SOHC and the "economy" form of VTEC. Note how ruler flat the torque curve is. From 1500 to 6500 the engine produces 90% or more of its peak torque. The little blip at 4000 rpm appears to be the VTEC transition, while at 5000 rpm the intake manifold butterfly valves open. Sweet. If we had any complaint about this engine it was that it wanted more revs - yep, that's about the only complaint."

Dyno plot.

http://vtec.net/articles/article-image?image=113992/03tovaccord6mtdyno.jpg

Theres more...
"We used some OBDII logging software to ensure that intake and coolant temps were consistent across all runs. The TSX was far easier to keep cooler as it shares a similar cooling system with the Accord, but produces far less output to tax the radiator with. We also checked tire pressures (37 psi hot on both cars) to further ensure that we controlled as many variables as we could.

After doing our baseline runs, both cars were also subjected to our traditional intake mod test, whereby we tweak the stock airboxes (or remove them) to see if there is any power lurking in the intake. The answer? A resounding yes. The TSX gained about 5 hp while the Accord picked up nearly 7. Imagine what a proper cold air intake will do!"

 

[thisaznboi88]

nice find. I wouldn't be surprised since the accord does have 10.1:1 CR. higher compression + higher grade fuel = A+. lol, but then again you have to factor in the head design, flow, and all that other stuff.

Just wondering was the CL also dyno at that same placed?

The HP different might be accounted for by the dyno being calibrated differently.

as for the 4000rpm that is when the butterfly open up on the intake manifold, and then vtec kicks in at 5000rpm.

 

[2000honda59]

I'm new to this Forum since I recently bought a 2006 Accord Coupe V6/6M even thought I used to have a Full Blown Turbo D16Z6 Civic Coupe EX that I sold about 4 years ago.

To the point, I became very curious about the performance of my car with regular or premium gas and checked out this forum and found two groups.
1-Those who believe on the statement that premium gas yield more power on cars that HAVE A KNOCK SENSOR like ours.
2-Those that think that it is sort of a fantasy or a placebo effect (Haters of the premium gas statement)

Interestingly I found some information regarding the claims of an Honda technician(That I believe is a Round Up/Proficient Engineer) named Asaki Yasuaki that premium gas yield an additional 10 HP. Some said that this guy was full of it and it was BS. Based on that, I took my time and went out for more factual data on this topic and found out that this guy Yasuaki Asaki, have a Patent on his name US 6947828B2 assigned to Honda Motor Co. LTD titled "Knock Control System for Internal Combustion Engines". I think this guy knows what he is talking about when he said that premium gas will free up some power on our engines.

The Patent information can be accessed with this link "http://www.wikipatents.com/US-Patent-6947828/knock-control-system-for-internal-combustion-engine/Page-21". More interesting, if you read paragraph #5 on page 21 it clearly explain the adjustment done by the ECU to the ignition timing based on the knock sensor signal. On a 10.0:1 compression ratio engine that is conservatively tuned for 87 Octane, a timing advance with higher octane gas will definitively yield additional power.

Food for thought...

so 91 does make a difference, some guy told me its just a waist of money and people just say that so people that have performance mods will think better gas, faster car.and then purchase high octain instead of regular for business, i felt a faster response when i slightly accelerated, the guy acted like i said i had a boost of NOS when i pushed the gas , he said it was in our heads thinking power

 

[Accordguy04]

I heard slightly diff. The stock 06-07 V6 put out 244 hp crank and I heard with premium it bumped it up to a nice even 250 crank.

 

[Markus]

Anybody really think they'll feel that supposed HP increase?

 

[jeffislouie]

You wouldn't be able to feel a 10 horsepower increase. No chance. Even the most highly calibrated butts would be unable to feel it.
I hate to be that guy, but while I am aware of dyno results showing as much as a 10 horsepower increase, I've also seen dyno results that showed a decrease in power as well as a 3 hp increase and no change.
I'm not going to buy it unless you can provide dyno sheets from the same car, one with regular gas and one with premium. So far, not one single person has been able to do that. Sure, I've seen dyno sheets that purport to show an increase in power, but dyno's aren't perfect. The same dyno on the same day can give different results for the same car. Dyno's need to be calibrated frequently and tend to be very inconsistent.
A 10 hp increase sounds like a lot, but in reality it is insignificant. Plus, the amount you have to spend to enjoy that boost is not a small thing - high octane gas can cost as much as 20-30 cents more per gallon than regular. Anyone who buys into this theory is sure to nail the gas a lot to test it, resulting in decreased fuel efficiency and, thus, more gas. Costs go up and add up and the results aren't significant.
As always, do as you please - but the idea that you can feel the difference just isn't realistic.

 

[thisaznboi88]

Anybody really think they'll feel that supposed HP increase?

Hello no. lol

But if it does work an extra 3 bucks for 10 hp is super worth it vs 300 for AEM v2 intake for lets say 10hp *yes Its not 10 but for the sake of comparison*

Now the j-pipe in comparison. You can feel that lovely tq as you chirp tires. hehehe

 

[jeffislouie]

Hello no. lol

But if it does work an extra 3 bucks for 10 hp is super worth it vs 300 for AEM v2 intake for lets say 10hp *yes Its not 10 but for the sake of comparison*

Now the j-pipe in comparison. You can feel that lovely tq as you chirp tires. hehehe

I have to say - I disagree.

Let's compare:

intake: $300
- one time purchase
- no additional costs ever
- something you can actually show someone (or that they can observe)

Using Premium: roughly $144 a year, every year
- cost continues as long as you use premium (increases operating costs)
- can't show anyone
- tough to prove

Premium costs around 30 cents more per gallon than regular, meaning every fill up costs more.

I'd rather pay the upfront costs.
If this is proven to work (again, still missing that piece) it really only pays off if you've already done other stuff to boost power.

 

[sodaks2k]

So where's the dyno sheet before they used the 91 octane? If there isn't one, then there is no proof that 91 octane yielded a higher hp number. So what if it put more power down than the CL-S. You can take two 03 v6's and they'll put down different numbers. Either way, IF you get 10 hp out of it that you're not going to feel, is it worth the money (as Jeff pointed out)?

so 91 does make a difference, some guy told me its just a waist of money and people just say that so people that have performance mods will think better gas, faster car.and then purchase high octain instead of regular for business, i felt a faster response when i slightly accelerated, the guy acted like i said i had a boost of NOS when i pushed the gas , he said it was in our heads thinking power

You should point out that you have a 2000 4 cylinder, not a 2003+V6. Again, READ the thread I linked for you. Your 4 cylinder will NOT gain power from 91+ octane fuel.

 

[jeffislouie]

so 91 does make a difference, some guy told me its just a waist of money and people just say that so people that have performance mods will think better gas, faster car.and then purchase high octain instead of regular for business, i felt a faster response when i slightly accelerated, the guy acted like i said i had a boost of NOS when i pushed the gas , he said it was in our heads thinking power

I just saw your cardomain and your car has the i4. The quoted statement was in regards to the v6 only. I4's have been shown, on the dyno, to have reduced power (and fuel economy) on premium fuel. something about the computer retarding the spark to compensate for higher octane than the engine was designed for.

There is no evidence whatsoever that your I4 gets any gain in power using higher octane gasoline. as a matter of fact, there is overwhelming evidence that running 91 in your car will reduce power and hurt fuel economy. Sorry dude - you've been duped...

From USA today:
"Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly or run as smoothly on premium, notes Gibbs, the SAE fuel expert.

High-test does have a potential fuel economy benefit. It is slightly denser than lower-octane gas, meaning there's a little more energy in a gallon. But the small difference is hard to measure in real-world use, and that same density can contribute to undesirable buildup of waste products inside the engine.

No data show that engines designed strictly for regular run better or longer on premium.

The Federal Trade Commission, in a consumer notice, emphasizes: "(I)n 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."

There is "no way of taking advantage of premium in a regular-grade car," says Furey.

"There is no gain. You're wasting money," insists Jim Blenkarn, in charge of powertrains at Nissan in the USA.

"No customer should ever be deluded into thinking there's any value in buying a higher grade of octane than we specify," says Toyota's Paul Williamsen, technical expert and trainer."

 

[sjlee]

No data show that engines designed strictly for regular run better or longer on premium.

I think that's the crux of the argument. If the J30 engine was designed for premium unleaded, then it would yield increased performance when using premium unleaded.

Granted, most people won't notice or be able to use 10 extra HP in everyday driving, but will notice the extra money they're spending on gas.

 

[shaunmac9128]

I think that's the crux of the argument. If the J30 engine was designed for premium unleaded, then it would yield increased performance when using premium unleaded.

Granted, most people won't notice or be able to use 10 extra HP in everyday driving, but will notice the extra money they're spending on gas.

If its designed to run on premium then you shouldn't notice an increase because you should be running premium I've actually noticed in motor trend a couple times recently that some of the higher end cars, when they list the engine specs/power they will list the power it makes on 87 vs 93 octane, just found that interesting.

 

[hillstones]

Obviously none of you are from California. If you were, you would not be wasting money on high octane fuel. It offers no benefit except to drain your wallet. Gas has shot up over the past month, 87 octane is about $3.20 per gallon. The Accord is designed for 87.

 

[AznX TL]

i just paid 3.30 for 93 a few days ago in PA. granted i dont have a 7th gen but i can feel the difference in WOT with premium vs regular when the car is underload, the power band is much smoother in premium as regular shudders a bit.

 

[jeffislouie]

i just paid 3.30 for 93 a few days ago in PA. granted i dont have a 7th gen but i can feel the difference in WOT with premium vs regular when the car is underload, the power band is much smoother in premium as regular shudders a bit.

No. You can't.
You think you can feel the difference. But you cannot. Unless you drive NASCAR or IRL, you are not a highly calibrated machine that can notice tiny differentials in power. The original claim by the engineer was for the V6 engine and represents ~ a 4% increase in power. In your car, that would be a tiny, tiny amount of hp.
Unless I'm mistaken, which is possible, your car is an I4. There is ABSOLUTELY no evidence, nor has anyone successfully claimed that running premium in the I4 is good for any increase in power whatsoever. The engineer whose quote started all sorts of hopeful experimentation was speaking ONLY about the higher compression V6 motor. All Accord 4 cylinders are designed to be run on 87 octane. There is no advantage to running anything higher grade (unless you are experiencing knock, in which case you should take your car to your dealer).

I wish the engineer guy had just shut his freaking mouth. All he's done is kick up a sh*t storm of threads on every message board dealing with honda, accords, vtecs, where some guy claims his butt dyno says that running premium in his I4 shows that his car is faster even though the engineer was talking about the higher compression v6.

:dunno:
:rant::rant:

:headbash::headbash:

http://www.usatoday.com/money/autos/2003-07-30-premiumgas_x.htm
http://www.consumerenergycenter.org/transportation/consumer_tips/regular_vs_premium.html
http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-premium-g
http://www.caranddriver.com/features/01q4/regular_or_premium_-feature