How improve gas mileage

[goco]

Did eny one try improve gas mileage with special air filters or high octane fuel. Tc come from Europe in my knowledge they do not have low octane fuel they starting from 90 octanes .so tring find reason why they recommend 87 octane fuel on USA, Any one have suggestion.

[hollowwood]

Not sure exactly what you are asking? In the US, 87 octane fuel is the normal fuel. If you have a high compression engine, or, one that has a carbon buildup, you need a fuel with a higher octane number. What you may not realiize is that the higher the number, the harder it is to ignite the fuel. High compression equates to higher tempertures in the cylinder before the spark plug can fire. This can cause the mixture to ignite too soon resulting in Pre-Ignition, or, knocking. Making the fuel mixture less prone to low tempature ignition by raising the octane rating, keeps the engine from damaging knocking and poor fuel milage. Carbon buildup can cause hot spots that will also cause pre-ignition. So, understand, lower octane fuel ignites easier than high octane fuel. Low octane fuel works best in a short stroke engine. High octane in a long stroke engine. Low octane burns fast, high octane burns slow. Not exact,but, close.

[103west43rd]

Keep in mind, the octane posted on U.S. pumps is the average of the MON method plus how it is meassured in Europe (RON method) divided by two. Look at the yellow sticker on the pump that displays the octane number. In little print under the octane number it shows R+M/2 as how the octane rating is calculated so 87 in the U.S. is not the same as 87 in Europe. RON method is used in Europe and is always higher than MON and the rating in the U.S.

Edited March 19, 2012 by 103west43rd

[iaanhayden]

Racing, braking and fast acceleration waste gas. Depending on the kind of vehicle, poor going by car customs can contrary sway fuel finances between 5% and 33%. Misaligned exhausts drag rather than of roll freely. Improper alignment can decrease fuel efficiency by as much as 10% - about 31 cents per gallon.

[Transit_jay]

I think the original question was, is there any mechanical way to improve performance. and I would like to know what others have found to work. My 2013 2.0L durotec seems to be the same as in my ford focus. Can the same mods be used-Breathers -Turbo-chips?

[robertlane]

I don't believe MRT has their Transit Connect exhaust out yet, but here's their URL;

http://www.mrt-direct.com/

[bikinchris]

The simplest way to improve performance at low cost would be to improve the engine breathing. Better intake through the use of cold air intake and free breathing exhaust. After those steps, chipping the computer would improve timing and engine management to improve performance, but I don't know anyone who makes a chip. hay, it's NOT a hotrod.

Besides all of the above can alter your warranty coverage.

[Johnyguy]

i would always use 93 gas in US gives you better mileage and better for the engine to burn .

[2013TransitConnect]

i would always use 93 gas in US gives you better mileage and better for the engine to burn .

Wouldn't you need to reprogram the engine for 93 octane fuel? I've heard reports of people using too high octane than what an engine was designed for and getting worse mileage.

[bikinchris]

Not just worse mileage, but amazingly enough MORE carbon build up. The Ranger 4.0L had this odd result when using 93 octane. I think the TC is built to be a work van, like other trucks and it doesn't need high octane fuel. Besides, if you do the math, any better fuel economy you find with the more expensive fuel actually costs more because of the price of fuel doesn't improve mileage enough to pay for itself..

[2013TransitConnect]

Not just worse mileage, but amazingly enough MORE carbon build up. The Ranger 4.0L had this odd result when using 93 octane. I think the TC is built to be a work van, like other trucks and it doesn't need high octane fuel. Besides, if you do the math, any better fuel economy you find with the more expensive fuel actually costs more because of the price of fuel doesn't improve mileage enough to pay for itself..

My TC manual says some knocking is normal so I stick with 87 octane.

[Johnyguy]

Not just worse mileage, but amazingly enough MORE carbon build up. The Ranger 4.0L had this odd result when using 93 octane. I think the TC is built to be a work van, like other trucks and it doesn't need high octane fuel. Besides, if you do the math, any better fuel economy you find with the more expensive fuel actually costs more because of the price of fuel doesn't improve mileage enough to pay for itself..

I just don't get it how a better quality better burning fuel causes carbon build up.I'm sure modern engines computer adjust to the fuel mixture accordingly.

Otherwise in Europe every car would have a carbon build up issue.

[Johnyguy]

Wouldn't you need to reprogram the engine for 93 octane fuel? I've heard reports of people using too high octane than what an engine was designed for and getting worse mileage.

In the tc specs at the ford website states that for the 1.6 liter turbo engine requires premium fuel to get the engine rated HP if you use regular fuel you get less HP.

So I would think if you use premium fuel in the 2.5 liter engine also helps to get slightly better performance and better MPG.

[Willie]

Johny:

The purpose of high octane is to allow engines with higher compression ratios to run without knocking, If an engine does not have a high compression ratio it cannot benefit from high octane fuel. This might help to explain it:

http://www.economist.com/blogs/babbage/2012/09/octane-ratings

[Johnyguy]

Hey that's makes sense because the 1.6 liter turbo engine Ford uses has a high compression.

Thanks

[Willie]

Sure, and though the turbo doesn't raise the actual compression ratio, it has essentially the same effect as well.

[2013TransitConnect]

Johnny,

The modern engine will adjust the timing but it still thinks its burning the lower octane and adjusts it incorrectly. You can reprogram the engine for higher octane and get better mileage and performance. I know the article says you don't but they were assuming you didn't make any reprogramming changes. In the 60's some fuel had an octane of 105 and the engines at the time would get better performance but less gas mileage -mostly due to the fact you drove it different. The article also said the octane didn't make a difference on the BTU's but that is not what most drag racers believe.

[Willie]

I'd place more credence in what fuel engineers think than drag racers. But thats just me.

[2013TransitConnect]

In this case I'm not doubting the engineers but rather the person that wrote the article. To a writer a figure of 10.00001 might be the same as a 10 but to someone trying to go a quarter mile just one thousands of a second faster than the other guy the numbers are different. I'm trying to read more about it as I'm just guessing on a higher octane having more BTUs. But I'm also thinking the higher octane might just be burning the fuel more complete and thus while it contains no more BTUs it does produce more energy through better burning.

[103west43rd]

If you Google "Does premium gas help in a car that is designed for regular"" you will see all the articles say no if your car is tuned and running properly. As for more energy in premium gas, that is also untrue. Here is an article from MIT......

What’s the difference between premium-grade and regular gasoline?

Premium gas has a higher octane rating that may—or may not—make it a good choice for your engine…

With slight variations—depending on the crude oil and the refining and blending processes used in production—all gasoline grades contain the same amount of chemical energy. When combusted, premium (high-octane) gasoline and the less-expensive (and less-glamorous) regular, and all grades in between, provide the same amount of thermal energy, or heat, which an engine uses to generate the mechanical power that moves a vehicle.

There is, however, another aspect to this question, notes Ahmed Ghoniem, the Ronald C. Crane Professor of Mechanical Engineering at MIT: How much of that raw heat energy can the engine actually convert into mechanical energy? “One can argue that using high-octane fuels in the right engine ultimately leads to more mechanical power from the same amount of fuel,” he says.

In other words, higher-octane fuel confers an advantage in some cars, but not others. It allows performance-oriented engines (specifically, those with higher compression ratios) to burn gasoline at higher pressures and higher temperatures. These conditions at the moment of combustion create better thermodynamic efficiency, so a greater percentage of the gasoline’s heat energy gets converted into motive power.

Octane rating is a measure of grace under pressure: how evenly a gasoline will burn under difficult conditions, like hard acceleration. Ideally, the vaporized gasoline inside an engine’s cylinder burns by the propagation of a wave of flame, ignited by the cylinder’s spark plug. This allows a smooth transfer of power to the engine’s crankshaft and the car’s wheels. But at higher pressures or temperatures, small pockets of gasoline vapor can prematurely explode, or self-ignite, creating a distinctive “knocking” sound, as well as potentially destructive shock waves.

Gasoline with a higher octane rating does not self-ignite easily, and burns more evenly than lower-octane fuel under harsh conditions, resisting detonation and knocking. Modern engines, with electronic sensors and controls, are very good at preventing detonation of lower-octane gas (this is why drivers no longer hear much knocking). But high-octane fuel is still specified when designers want to achieve better acceleration and power output, and when they are willing to accept a slightly bulkier and heavier engine with higher operating costs. — Peter Dunn

Edited August 14, 2014 by 103west43rd

[2013TransitConnect]

Thanks. That makes sense. But what makes me wonder is that diesel fuel uses a cetane number that is similar to octane and a higher cetane number gives a very slight improvement in BTU's. Also some of the additives to gas that gives it a higher octane will increase the BTU's because it displaces some of the gas's volume. But on the other hand some additives like ethanol can also reduce the BTU's per volume.

If I had to put money on it I would go with the higher octane being more efficient in burning the fuel and like the article says not an increase in BTU's.

Also from what I've been led to believe is that an engine tuned to run on a lower octane will not benefit from using a higher octane but an engine tuned to run on a higher octane will not run as good on a lower octane. The higher compression might require a higher octane but if the timing is changed on a low compression engine you can benefit. But you do have to make specific changes.

And thinking about it further I am basing my thoughts on fuel in the 60's which had lead in it that eliminated knocking.

[Willie]

Also from what I've been led to believe is that an engine tuned to run on a lower octane will not benefit from using a higher octane but an engine tuned to run on a higher octane will not run as good on a lower octane. The higher compression might require a higher octane but if the timing is changed on a low compression engine you can benefit. But you do have to make specific changes.

And thinking about it further I am basing my thoughts on fuel in the 60's which had lead in it that eliminated knocking.

Now here, you are on the right track, if by "tuned" you mean modify the spark timing.

I once owned a turbo Mustang equipped with a special distributor which changed the spark timing whenever the turbo spun up in order to prevent knocking. So yes, it could be done (actually pretty easily during pre-electronic days). Today it would take a "chip" or other method to change the electronic parameters.

You are also correct that tetraethyl lead was the original additive used to boost octane. This was done when high compression engines were developed.

Here is a super article on the introduction of leaded gas: (Actually this entire book is fascinating history.)

http://www.theautochannel.com/mania/industry.orig/history/chap7.html

Edited August 14, 2014 by Willie

[2013TransitConnect]

Thanks for the link Willie, that was good reading.

[johnsonmy]

There is a small "snorkel" coming from the air cleaner housing and ending at the inner fender. It looked substantially smaller than the intake conduit going to the intake manifold. So I removed it. Better throttle response, stays in overdrive longer on inclines. And with our current cold weather (20 degrees tonight), it almost feels like a low pressure turbo coming out of the toll plaza! Cheap performance improvement.

[Willie]

Johnsonmy, I think you may be on to something here.

To my understanding, those intake snorkels are generally used to reach cooler intake air. The warmer air from the engine compartment is disadvantageous once the engine has been warmed up.

I bet in hot weather you would find that the engine will perform better with the snorkel in place, but in this frigid weather even the air close to the engine was plenty cold enough.

It might make sense to disconnect the snorkel for the winter though. It would be great if there were something good about this weather!!!