had to throw that in ... wish i was you though with the free gas , but if i was i dunno if would have tradded in the (2000 jeep (paid off)) for my much loved scion !!!this wagon rocks ( tapping fingers waiting on wheels and tires and springs in the mail)

 

I know man, it's cool! I really hate buying gas! Like if I'm off somewhere, not close to home, and have to buy it! That really sucks!

 

Depends on how the basic curves for the engine are set up.

In one vehicle I had previously that was designed to run on 87 (and would probably run on anything from Vitalis to avgas) there was a noticible difference in running high octane fuels because it was designed to advance it's timing until just at the start of ping and hold it there. It adjusted the timing if each cylinder individually based on the knock sensor on that cylinder.

I doubt the Echo engine is designed/set the same way. I suspect it is designed for best performance with an 87 octane fuel, and the knock sensor is set as a 'safety' that will simply retard timing if knock is detected.

Then again, the only way to tell for sure, without getting the word from Toyota, is to dyno a stock engine on different fuels to see what happens.

Thing is, with multiple knock sensors (one per cylinder) and computer curves designed to do it, this little 1.5 *could* take advantage of higher octane fuels. We just don't know what the engineers did in this case.

 

Well put, Tomas. If the knock sensor is only there as a safety, we get what we get, and that's 108 HP on 87 - or any other octane - and that only under ideal conditions.

Hopefully, that's not the case. I'd be surprised if Toyota added the sensor and related software just as a safety, but maybe so. At the least, it eliminates potential customer complaints about knocking and/or any requirement for high octane, at not much cost to Toyota.

I'll try the good stuff soon and see if I notice any difference, particularly in the "lugging zone" - ~2000-2500 RPM on a grade.

 

I've tried multiple grades of fuel at different times and it didn't make enough difference to make it worthwhile. Performance and fuel milage didn't go up or down depending on the octain rating so if you do use the more expensive stuff you are just throwing money away. Nuf said.

 

gslippy is entirely correct. Add in:

-Ever notice how your car runs sweeter in cool, wet air? Or in the rain? The excess of moisture in the intake air has a modifying effect on the speed of the combustion process. This is quite noticable, and has been noted and exploited by aftermarket gadget makers since the dawn of automotive history.

The molecules of water vapor seem to act like spacers, having high heat adsorbtion, perhaps.. and so, slow down the progression of the flame front by some large number of microseconds. Result: A better push on the piston crown over larger number of crank rotation degrees, as gslippy noted.

Also in the formula: compression ratio vastly affects speed of the combustion. More on that later if interest is there.

 

87 for me

 

SciFly I'm glad you have $'s to waist on gas.(as if it didn't already cost too much) I'll spend my savings on mods and have the same performance as you with my 87 octain It's only money right

 

22% of the people responding to this poll have wasted money.

 

My original main reason for this post was to see if running 93 would hurt the engine. Even with "throwing away" the extra $.20 it appears that some say it won't hurt and will help regardless of the fact that it won't help in leaps and bounds. Not sure how the "jerk at work" is smarter than me as no one has stated that it will hurt the engine. Not to mention the fact that he wrote the post calling himself that.

 

??? It will hurt your wallet and it won't improve the performance. So, why spend money on something that does nothing. Please explain? I don't understand why 20% of the people would spend money on something that has no benefit? OH well, I give up trying to explain it.

 

87. As far as type. What evver gas station I am closest to when the light turns on.

 

So I spend an extra $100 annually for gas. Whoopty doo. Maybe most of you are right. I should drop to 87. While I'm at it, I can just drop the insurance on it. That'll save me $1200 annually since I don't use it (the insurance). Never wash it again... that'll save some time and money. Oooh Oooh! I'll never eat out again. From now on its Ramen Noodles. No more beer! No more soda! No more pizza! Hell, I'm gonna be rich.

 

Be aware that the brand of fuel you buy may not really be that brand. Many gas haulers "trade" fuel - i.e. so that Hess gas you buy may be Exxon etc.

 

I'm sure there are plenty of charities that would love to get a hundred dollars from all the fools that waste money on premium fuel. At least the money would do some good there.

 

I already give to charity. What's your next idea?

 

Spend all you want on gas. I don't really care Just stop telling other people that there is a benefit to burning premium when there really isn't. Remember if people hear enough BULL$HIT they start to believe it. I can't help that 20 percent of the people in the poll are flushing money down the drain and making the oil companies richer. Some have more money than they know what to do with.

 

UMM... i would much rather throw away my money by putting premium in my tank than ... buying ... owning ... or listening to a gehetto sound system like yours ... haha , OMG STOP... and BTW if you werent working your "BAD TO THE BONE" audio system so hard , you may get better mpg. peace

p.s. i bet jethro b has a grounding kit installed... AND OMG
A "electric supercharger" hahahahah

 

I would suggest before calling BULL$HIT on people to do a little research so you know what you're talking about -- to quote Shell Canada's website (http://www.shell.ca/code/motoring/tips/gasoline.html):

"Engines in vehicles built for sale in North America are designed to a specified octane requirement to make sure they don't knock or ping (engine knocking reduces the amount of power it can deliver to turn the wheels). Once that octane level has been met, in normal instances your car will not experience more power or better mileage if you use a higher octane fuel.

In other words, if your Canadian vehicle owner's manual specifies an octane rating of 87, running on gasoline with an octane rating of 89 or 91 or more will normally not make a difference.

However, there are some exceptions to this, and it must be noted that if the owner’s manual specifies using gasoline with an octane rating of 89 or 91, then that’s what you should use because that’s what the engine is designed and tuned for.

One - and a very important - exception is that when a vehicle gets older, the normal build-up of fuel- and lubricant-related deposits in the engine can increase the fuel octane number a car requires to prevent engine knock. For this reason, if a car more than a couple of years old experiences engine knocking, the problem may be solved simply by moving to the gasoline with the next-higher anti-knock index.

You will also benefit from a higher octane rating if:

the engine is knocking on the gasoline you are using, or

you have knock sensor ignition that can take advantage of higher octane values at times of peak demand, or

high summer temperatures, mountain driving, pulling heavy loads (including loaded roof racks) has temporarily increased your engine’s anti-knock index requirements.

While fuel with a higher octane rating cannot of itself deliver more power, in the above circumstances it can give an engine a greater ability to resist knocking, thereby helping it to deliver the full measure of power it is designed and tuned to provide.

In these cases, where drivers require their vehicles to continue providing peak performance despite challenging driving conditions, for improved responsiveness we recommend using a mid-grade fuel like Shell Silver (octane rating 89) or a premium fuel like Shell Optimax Gold (octane rating 91) gasolines.

One other exception is found in high-performance vehicles. The use of more complex computer algorithms in their engine control systems to control spark timing using one or more knock sensors, enables better performance on higher-octane fuel. Owner’s Manuals for most of these vehicles will specify use of 91 octane fuel."

So while you're right that the octane rating in and of itself in normal circumstances won't provide an improvement when using higher octane gas in a vehicle, there are a number of exceptions where there is an improvement (gslippy's knock sensor equipped engines example being one). Laugh all you want, but you're wrong, and I can tell you flat out that here in PA where we got long, steep ___ hills, there most definitely is a noticeable difference between 87 and 93 oct when climbing them. You can argue all you want, but you're not gonna one-up a company that makes gasoline.

 

Are you sure you couldn't come up with a few more paragraphs of info? No matter what techno bull anyone comes up with 87 octain is all these little econo boxes will ever need so quit trying to convince the other 80% into thinking they will see any seat of the pants performance out of higher octain fuel.
This topic is just going round and round and some people just don't get it and that is fine. Just keep spending $$$'s on fuel you don't need. The oil companies don't care and neither do I anymore. See if I try to help anymore! And to those 20 % "Bless Your Hearts" Your Special! especially professor_xb