Will going to a higher gas make any difference towing with a V6?
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Technically. YES! Higher octane gas has a higher "energy" output. That said, we are talking percentage points and possibly not perceptible. Your ECU has the ability to adjust the combustion cycle to account for the different grades of fuel commonly available in the United States. The US has high grade fuel. Its quality is very uniform where in other places, it is not.
So. Yes. You would likely see a percentage increase in MPG; but I am not sure in towing ability; you would notice except at a math board.
So. Yes. You would likely see a percentage increase in MPG; but I am not sure in towing ability; you would notice except at a math board.
Toyota GR engine - Wikipedia, the free encyclopedia
According to Wikipedia (not that it should be trusted), going to 91 from 87 generates a few percent more torque at slightly lower rpm in certain applications (not that this bears true for the 4Runner). I don't really understand how, since octane rating has nothing to do with how much "energy" the fuel has, but rather how hard it is to ignite. The reason high-power cars require 91 is that they can increase the compression ratio without the gas prematurely igniting. If you put 87 in these cars, they have knock sensors that will re**** timing, which will prevent knocking but also reduce power and efficiency. Thus, theoretically, putting 91 in a car designed for 87 wouldn't make a difference since it will still detonate at the same point when your car ignites it. My guess, however, assuming some veracity in the wikipedia data above, is that in this day and age of super-advanced ECUs, engine sensors, and variable valve timing, Toyota's engineers have figured out a way to take advantage of using higher-grade fuel to squeeze out a few hp and ft-lbs. I have no idea how.
So to answer your question, at worst, using 91 won't do anything, and at best, assuming Toyota engineers figured out some trick way of taking advantage of 91 octane's ignition properties, you might get a few extra ft-lbs out of it, which will never hurt for towing. For me, next time I tow, I'm going to try 91 and see if it makes a difference. My guess is that I won't notice any difference, or maybe I'll pay a little extra just for the placebo effect, but for the extra buck or two at the pump, I'll try it out.
According to Wikipedia (not that it should be trusted), going to 91 from 87 generates a few percent more torque at slightly lower rpm in certain applications (not that this bears true for the 4Runner). I don't really understand how, since octane rating has nothing to do with how much "energy" the fuel has, but rather how hard it is to ignite. The reason high-power cars require 91 is that they can increase the compression ratio without the gas prematurely igniting. If you put 87 in these cars, they have knock sensors that will re**** timing, which will prevent knocking but also reduce power and efficiency. Thus, theoretically, putting 91 in a car designed for 87 wouldn't make a difference since it will still detonate at the same point when your car ignites it. My guess, however, assuming some veracity in the wikipedia data above, is that in this day and age of super-advanced ECUs, engine sensors, and variable valve timing, Toyota's engineers have figured out a way to take advantage of using higher-grade fuel to squeeze out a few hp and ft-lbs. I have no idea how.
So to answer your question, at worst, using 91 won't do anything, and at best, assuming Toyota engineers figured out some trick way of taking advantage of 91 octane's ignition properties, you might get a few extra ft-lbs out of it, which will never hurt for towing. For me, next time I tow, I'm going to try 91 and see if it makes a difference. My guess is that I won't notice any difference, or maybe I'll pay a little extra just for the placebo effect, but for the extra buck or two at the pump, I'll try it out.
Somewhat of a broad question... Will it give the engine more power or torque? Will it help with MPG while towing? Will it increase the towing capabilities? This could go in so many directions, but in the real world it probably wont do anything but put a bigger dent in your wallet.
Will it give the engine more power or torque? Not more than Toyota rates the engine from the factory. Premium fuel is required per Toyota for optimal performance and I'm sure all the numbers they gathered were while using premium fuel. This would be the same case for towing capacity, which is probably determined more by other vehicle components (frame, suspension, and vehicle weight) then the engine.
Will it help MPG while towing? Sure, but I doubt that you would notice, and not enough to make up the price difference between premium and the cheap stuff.
What would make a difference and wont hit your wallet is your driving style. execution of stopping and starting will be noticed on your gas gauge. Using the extra weight to coast is helpful and giving extra time and space so that you can time lights and hold momentum up hills is probably going to be your best bet.
Will it give the engine more power or torque? Not more than Toyota rates the engine from the factory. Premium fuel is required per Toyota for optimal performance and I'm sure all the numbers they gathered were while using premium fuel. This would be the same case for towing capacity, which is probably determined more by other vehicle components (frame, suspension, and vehicle weight) then the engine.
Will it help MPG while towing? Sure, but I doubt that you would notice, and not enough to make up the price difference between premium and the cheap stuff.
What would make a difference and wont hit your wallet is your driving style. execution of stopping and starting will be noticed on your gas gauge. Using the extra weight to coast is helpful and giving extra time and space so that you can time lights and hold momentum up hills is probably going to be your best bet.
Absolutely NOT....Higher octane is for anti-knock...NOT PERFORMANCE.
If the vehicle is designed to use high octane then you should because using a lower octane gas could cause knocking (especially under load) and thus causing the anti-knock sensor to re**** the timing (thus lower performance).
But if you vehicle is designed to run on lower octane then using higher octane will have ZERO effect on performance.
Octane rating - Wikipedia, the free encyclopedia
High Octane
High Octane Fuel Q&A Feature with Rockett Brand Race Fuel - Motor Trend
» High Octane Gas Myth
jetboy1975
New member
The only real difference is how much more the trip is going to cost you using premium gas!
Premium where I live is consistently 20 cents/gal more than regular. Assuming you put 18 gallons in, that's $3.60 per tank more. Next time I tow, I'm willing to spend $68.60, as opposed to $65, to fill the tank just to see if it makes a difference to me.
Probably right, that's why I'm going to pay the staggering price of $3.60 to try it out. As I said, I don't understand how a car rated for 87 can generate more torque by using 91, but I wouldn't put it past Toyota's engineers who are smarter than myself to figure something out.
ClockWork
Banned
The V8 is stated to have better performance figures using higher octane gas. It's not defying the laws of physics. More complete combustion at the right instant takes place with higher octane gas.
After many a road trip - putting 93 in my car pays for itself with the increased mileage that I get.
KidVermicious
New member
You can't get better performance using higher octane than the engine needs. If your engine is designed for 87 octane, 89 will not perform better. If your engine is designed for 91, 87 will perform worse.
What's the recommended octane rating for the V8?? I thought it was 91 octane??
If it is..then as I said in my earlier post...using a LOWER octane when the vehicle is designed to run on 91 octane could result in less performance because in order to prevent pinging the ECU backs off the timing...this will result in lower performance and torque.
If the recommended octane for this vehicle is 87 octane...then using a higher octane will have no effect what-so-ever in performance or gas mileage....There is however a caveat to this....After many thousands of miles of use...combustion chambers sometimes have carbon buildup. This carbon buildup may increase the compression ration. Increase in compression ratio may mean you'll need an increase in octane...but that would be an extreme case.
Why would Toyota put in the owners manual that, although the engine is rated for 87 octane, you can use 91 octane or higher for "improved performance"? I still think there could be something to be said for compression, knock sensors, variable timing, and whatnot that allows Toyota to adjust the timing and/or compression on the fly to eek out a little more from 91 octane.
But I'm the first to admit I could be wrong.
But I'm the first to admit I could be wrong.
04_4runner
New member
I have the V8 so I can't talk directly to the original post about towing with a V6. I can say that I experience a noticeable difference in performance when using premium fuel. I always track my fuel consumption (fuelly.com) and I do NOT get any better fuel economy with premium. I tracked close to 1000 miles using Mobil premium verses 2000 miles using Mobil regular. City or highway mix makes a big difference, fuel type did not.
ClockWork
Banned
There was a document FROM Toyota with increased torque and horsepower figures with higher octane fuel. I can't find it but I'll continue to dig around.
87, Lexus says put in 91 but it makes no difference. These V8's are designed for the third world - they'll run on anything. They do not have an EGR system ultimately reducing crud buildup.
Well I did.
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http://www.toyota-4runner.org/852610-post29.html
According to that post, that member seems to think premium should be used for compressions of 10:1 and above (no word on his qualifications to offer that opinion). Additionally, the GR-FE motor uses a 10.0:1 compression ratio. The factory service manual states that the GR-FE's octane rating is 91. http://www.ncttora.com/fsm/2003/4runner/215/ncf/1gr-fe_newfeatures.pdf
Perhaps the answer is that the engine is designed to handle 91 octane fuel. However, telling customers they have to use the "expensive stuff" is a turn-off to some buyers, especially for a brand that markets itself as being "sensible" and pedestrian. Therefore, they rely on knock sensors and ret@rd the timing so as to handle 87 octane. This way, your average daily-driver can fill it with 87 and the car will simply adjust the timing accordingly, but if you put 91 in it, the car can advance the timing and take full advantage of the higher compression.
Again, this is all speculation on my part and I have no facts to confirm this.
FWIW, the inline-6 in my other car has a compression ratio of 10.5:1 and requires 91 or higher.
According to that post, that member seems to think premium should be used for compressions of 10:1 and above (no word on his qualifications to offer that opinion). Additionally, the GR-FE motor uses a 10.0:1 compression ratio. The factory service manual states that the GR-FE's octane rating is 91. http://www.ncttora.com/fsm/2003/4runner/215/ncf/1gr-fe_newfeatures.pdf
Perhaps the answer is that the engine is designed to handle 91 octane fuel. However, telling customers they have to use the "expensive stuff" is a turn-off to some buyers, especially for a brand that markets itself as being "sensible" and pedestrian. Therefore, they rely on knock sensors and ret@rd the timing so as to handle 87 octane. This way, your average daily-driver can fill it with 87 and the car will simply adjust the timing accordingly, but if you put 91 in it, the car can advance the timing and take full advantage of the higher compression.
Again, this is all speculation on my part and I have no facts to confirm this.
FWIW, the inline-6 in my other car has a compression ratio of 10.5:1 and requires 91 or higher.
I'd very much like to see this...and a detailed explanation on HOW this is possible. Octane is NOT and NEVER have been used to increased performance...it's ONLY FUNCTION is to prevent engine knock in higher compression engines.
http://mn.gov/commerce/weights-and-measures/images/OctaneFacts.pdf
From the FTC...
The Low-Down on High Octane Gasoline
From the EPA...
Your Car and Clean Air: What YOU Can Do to Reduce Pollution | Consumer Information | US EPA
More...
http://www.wisegeek.com/what-is-high-octane-fuel.htm
From Toyota...
http://www.autoshop101.com/forms/h59.pdf
In conclusion...if you get better performance and better gas mileage by using a gas with a higher octane then what is rated for your vehicle...there are only 2 possibilities..
1) The gas you're buying is NOT actually the right octane rating. This is rare since most if not all states monitor this.
2) You have a problem with your vehicles engine...get it checked out.
ClockWork
Banned
Yes but the fact that knock is not an issue with the higher octane gas means that the engine does not have to ret@rd the timing. Therefore you get better performance.
That's called REVERSE logic.
If your vehicle is designed to run on 87 octane then the engine WON'T knock and the knock sensor WON'T ret@rd the engine timing. So 91 octane or 87 octane will make ZERO difference in performance....since NEITHER will cause engine knock. If engine knock occurs on an engine that's designed to run on 87 octane when the gas is 87 octane...then the engine needs to be checked out (SOMETHING IS WRONG).
