I'll have to thumb through it again, but I know it doesn't say "Premium Unleaded Fuel Only" anywhere around on the gas cap, but the point I've made is still there. I didn't suffer a performance drop using the lower octane.

As someone else has stated, the high performance cars that Honda made REQUIRES higher octane fuel. With the S2000 and Type R that have 11:1 compression, you always need higher octane fuel.

 

The manual calls for premium with fairly strong words. (like if you can't get premium only get a partial tank).

Lower octane can cause certain problems.

At best, the knock sensor will kick in and retard the timing. This will cut your power. (timing and other ECU adjustments)

Some of those ECU adjustments could also lead to faster fouling (like if it richens up the mixture).

Worst case the computer can't adjust enough and you get knocking. A little knock here and there is ok, but chronic knocking can definetely harm an engine.

If it was MY Z I wouldn;t put the 87 in it. That is just my opinion.

You need to find a friend with a big SUV (like mine). On "gas day" you swap cars. He fills your little Z with premium and you fill his big SUV with 87. Win-Win.

 

Isn't the compression in our cars 10.3:1?

 

now this is not to get on anyone's case, but think of it this way.

The Z has a 17 gallon fill up usually for me. Gas in MI is INSANELY expensive ($1.90 for 87 and 2.10 for 93) right now (I KNOW in other states it is worse, but in MI gas usually NEVER goes above $1.90 for premium.) So everyone is going on about how they drove 20 miles from home to get gas at a $0.05 cheaper station than local ones. They also think I am NUTS for buying premium.

I actually have to explain to people that the penny pinching they're doing is LUDICROUS. The difference between 87 and 93 octane gas is $0.15. Now multiply that by say 20 gallons (easier roundoff) You're looking at $3.00 a week difference in gas (I use a tank a week, I'm conservative I guess.) WHOOP DEE DOO $3.00!!! people spend TWICE that much EVERY day on CIGARETTES in MI. WHY is everyone flipping out over the difference? I also have fun explaining to the people who drive the 20 miles for cheaper gas that the fuel they're wasting going out to the trip costs them the money they saved and the fuel they spend going home is a direct loss.

If people would only sit down and do the math life would seem simpler. Instead I get to hear coworkers CRYING about the price of gas while they're puffing away on cigarrettes (can anyone tell I'm an avid non smoker? I don't mind smokers I just think it's ironic how they consider their vice a necessity yet they b!7ch about gas prices.)

 

One of the Most Idiotic comments I've heard here.. Hahaha I guess some people just don't know much about other cars.. <SIGH>

 

I'm simple.
The manual says to use premium.
I use premium.
Premium makes me go.

(For Star Trek fans, If you don't get it, don't worry about it.)

 

For me, I drive a total of 100 miles a day, and I fill up almost every third day. $3 saved can go a long way.

 

AND IT'S COSTING ME $2.30 A GALLON!!!!!!!!!!!!! I hate this ****ing state, this ****ing Bay Area, I hate it anymore, JESUS!!!
I don't know if he had anything to do with it, but the soon to be not a governor is a ****ing MAROON!!!!! Ok, i feel better now.

 

The higher you rev the engine with 87 octane fuel, the greater chance you will have knocking. So if you where to keep it under 3000 rpms for the most part with the free fuel, it would be pretty safe to say it wont hurt the engine.

Now if you like to redline it with the 87 octane fuel and you are not over ~6000 feet of altitude, you would most certainly have engine problems later on.

 

****ing putting God damn corn in my gas, JEEEEEEEEESUS CHRIST!!!

OK, now I really feeeeel better now.

 

After reading this I tried putting the normal stuff in my engine (I have my Z for about 10 months) which around here is 89 octane and I haven't heard ANY pinging.

http://www.motortrend.com/features/n...41/index3.html

Quotes from the article :
___

" advantage of premium-grade gas is that it allows automakers to advertise a few more horsepower by designing and tuning engines to take advantage of premium's anti-knock properties. But auto engineers generally agree that if you use regular in a premium engine, the power loss is so slight, most drivers can't tell.
"

"Today's engines use highly evolved versions of a device called a knock sensor to adjust settings automatically for low-octane gas. And more engine control computers have adequate memory to allow separate sets of instructions for various octanes. The engine control computers keep pushing to maximize performance on whatever grade of fuel is used.

Extreme pressure inside the cylinders causes knock, which is the sound of the pistons literally rattling inside the cylinders. Too much too long can damage the engine. A little now and then won't.
"

"Burning regular when the owner's manual specifies premium won't void the warranty, nor damage the engine, even the most finicky automakers say. "You're giving up perhaps just a little bit of performance that a customer wouldn't really even notice, it's so slight," says Furey."

"All Porsche engines are designed for premium, too, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development"

"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."

___

I had always put the good stuff in my Z before reading the article and doing my own tests. I went on a nice road trip recently and try to gun it and still heard no strange engine noises.

 

Exactly. I had taken the car to redline several times with 87 octane and there was virtually no difference between that octane and 91 octane.

And here's the kicker:

A Nissan guy saying that there is no gain on premium fuel. Surely he doesn't know what he is talking about!

 

The car is designed for Premium but nissan didn't think of that so It just says it on your gas lid. But I would keep putting in 83

 

I still load my Z w/premium, but as this article shows, the quality of regular gas these days is so good you don't really need to.

http://www.caranddriver.com/article....&page_number=1

 

There is do difference (power output) between std fuel and premium UNTIL the knock sensor kicks in.

IE. the moment there is pinging your timing will be retarded and you will lose a tad of power and kept in the safe zone.
If you are at high altitude and/or low temps you will most probably be safe with std fuel.

If you tune your car to 93oct, then you need to stick to it. And on very hot humid days you may need to add an octane booster to be safe... It's not rocket science, just common sense.

I don't know much about US fuels but in Australia we have 2 ratings on fuel RON and MON... Ron is for low rev detonation resistance and MON is for high rev det. res.
All our fuels fall short in their MON rating and thus if you race your car it is best to add an octane booster which will really give the MON rating a huge kick.

eg... your 92-93oct = our 98 RON 86 MON premium

 

Zuff, are we able to use the 95 RON Octane petrol here in Australia?

 

Yep but man is it getting expensive

 

Umm, free gas (87) versus 2.50-3.00 per gallon (91-93)?? I wouldn't blink putting the 87 octane fuel into the car. If the car is stock or some slight NA modding, I wouldn't even care if I drove it hard. The one NA mod that I would start to worry about is the ECU reflash because the fuel mapping and timing are changed and now a little more aggressive and the system may not respond the same way with the different gases. Save your money on the 87 now while you can and use it to pay the car off or buy some mods later.

 

+1
Be nice to everyone!
I figure you can use 87 as long as you don't like redline it every stop light. I'm sure it has some kind of effect otherwise it wouldn't be recomended in teh manual to use 91+. But i used 87 in my moms 03 maxima, same engine too, and it ran perfect in costal NJ (low altitude, mediocre weather)

 

This thread is ridiculous...87 octane on our Z's???