ls1charged

iTrader: (8)

Dont waste your money. Like most everybody nowadays, we all want to get better gas mileage. I was doing some searching to try to see if any of these things were legit and ran across this website and thought i might share what i found.
http://www.popularmechanics.com/auto...s/1802932.html

Shooter_Jay

I disagree with his conclusion. If you have a restrictive intake and you unrestrict it you can increase gas mileage on the same amount of gas more than 1%.

mycamaroSS

iTrader: (4)

way too much reading for me haha

Vicinity

iTrader: (7)

It says nothing works.

redls1bird

iTrader: (1)

In actuality, your wrong. The engine computer ( if your using one) doesnt really care for the most part about the amount of air entering the cylinder. It just wants to see the right amount coming out of it (indicated by the o2 sensors). If you "unrestrict" a restricted intake manifold, more air will enter the cylinder with the same amount of fuel. The combustion process will yield a more oxygen rich exhaust, which the computer will interpret as the motor running lean and will add fuel, decreasing your economy.

Shooter_Jay

I disagree. An intake that flows easier should allow you to make more hp with the same fuel, which means you can make the same power with less fuel. Yes you can use more gas for the same amount of pedal, but you could do the same power giving it less pedal.

redls1bird

iTrader: (1)

What your saying is true, only if the engine computer didnt cut back fuel, which it does. If your intake is restricted the computer will see it and roll back injection pulsewidth etc etc. What your scenario depicts is peak horsepower loss due to lack of airflow. You must have enough air to support the fuel being used. Thats why superchargers and turbos work so well. More air in allows more FUEL to be burned resulting in higher horsepower numbers.

If you have a carbed vehicle, your scenario is much more likely.

Shooter_Jay

what, you started with saying you disagree, but then what you said agreed with what I said. But the first part you have it backwards. With a freer flowing intake, the computer will allow more fuel to match the more air. But you are making even more power, so need less pedal to get the same power and using less gas. You can get worse gas mileage now, but for the same amount of power you will get better gas mileage, get it?

redls1bird

iTrader: (1)

The thing is, your thinking that the pedal controls the gas. It doesnt, It controls the air flow. The computer controls the gas. I know what your thinking, but it doesnt work quite that way.

Yes, a restricted manifold reduces airflow and power.
The computer will reduce the amount of gas you are using, hence the loss of
power.

In that case you will have to push harder on the gas pedal, allowing more air into the manifold.
The computer will increase fuel to match the air, giving you more power.
You will have to open the throttle further than usual to make the same power, but your
rpms will be the same and so will your fuel useage.

The big part of this is stoichiometry. Thats 14.7 parts air, to 1 part fuel. Your engine computer will provide that no matter what the air and out is, unless you have a broken part/sensor.

Thats the one part that your missing is even if you have to press on the gas harder, your not i ncreasing gas useage, just pedal useage. Once again, your peak horsepower will suffer but not your economy.

Shooter_Jay

No, actually your missing my whole point. We agree the computer will add more fuel relative to the amount of air allowed by the tb.

The point IS, if you put a half size intake, the engine has to work harder to suck the air through the straw. So it's losses are greater, more fuel is wasted on the sucking action. Reduce that waste, and increase your efficiency. So the free flowing at half throttle will have the same power as the half flowing one at full throttle, but use less gas due to the better efficiency.

That statement doesn't make any sense. You are just bringing a bunch of confusion to a simple fact.

redls1bird

iTrader: (1)

Hence why most people who use these gas saving devices, its so simple they think they know better than the people who designed them.

Its just like breathing through straws. Say you had two straws in your mouth and you had to breathe only through them. They are a restriction. If your just walking around or sitting, not exerting yourself, youll be fine. You couldnt run a marathon like that though. It would only hurt your peak performance, not lower end performance.

I never intended to argue with you about this. Sorry that i am being confusing and missing the point.

Shooter_Jay

ok, so looks like we might agree based on what you said there...

Low in the powerband, the half size intake flows enough air for it to work efficiently. But once you get to the point in the powerband where it is a restriction, above that point, is where I am talking about.

vaticano

iTrader: (8)

I adjusted my tranny settings and picked up 3 mpg highway in my truck.

bww3588

iTrader: (49)

actully, no. the engine does not suck air in, the atmosphere pushes it in. hence why there is a vaccum in the intake. using your logic, the engine would starve at anything over idle considering there is virtiually no manifold vacuum after part throttle. there is always ~14.7 psi in the outside air, with a vacuum present in the intake, that 14.7 psi wants in. when you hit the throttle, that vaccum drops because the throttle plate is opened to the point where atmosperic pressure over comes intake vaccum.

the engine is not working to suck air, the atmosperhe is working to push air to a point of more vacuum. so no more fuel is used to "suck the air."

the engine just wont get the air it needs to run at its potential, the computer will simply cut the fuel to maintain stoich. i bet if you put a straw from McDonalds in place of your bellows between the TB and MAF, and sealed it up, i bet you wouldnt see a drop in economy at all, however your power will suffer dramatically.

EDIT:

we might not go that far with the straw, that might totally starve the engine of air needed to run, but im willing to bet with someone, if they take their lid, FTRA (or equivelant), smooth bellows, descreened MAF, ported TB, etc off and replaced it with totally bone stock as a rock intake components, and dynoed it like PM did in the article, im willing to bet economy will be the same, even if power suffers.

Shooter_Jay

I think we can agree that the term suck describes flow towards lower pressure. I do know that sucking is not pulling. But after combustion, there is lower pressure in the cylinders which allows atmosphere to push intake charge into the cylinders. So whether you call it sucking or go through the whole explanation of flow towards lower pressure, that means the same thing, the science of what I said is still valid.

Shooter_Jay

If any of you like, you are free to believe that a restrictive intake will not give you worse gas mileage for the same power output. No skin off my back. I think those in the know will agree with me.

bww3588

iTrader: (49)

what your saying doesnt make sense. less air=less fuel=more air=more fuel. regardless its going to run at 14.7 A/F. if an engine gets more air via a less restrictive intake, its going to dump more fuel, regardless of fuel delivery method. it has to compensate for the more fuel or it will run lean, also by the same respect, an engine getting less air, via a more restrictive intake will dump less fuel. otherwise it would run pig rich. wether a computer does it for you by reducing PW on the injectors, or if you have to get under the hood with your trusty flat blade and do it yourself. inorder to maintain 14.7 A/F ratio, you have to either increase fuel, or decrease it with the changes in air flow.

as long as there is enough fuel and air to feed the cylinders, it doesnt matter how much air and how efficient its getting there, if its running at 14.7 A/F, its going to get the same economy provided its driven the same.

Shooter_Jay

The last time I'll say it. Forget about more fuel let in, less fuel...ecu correction, suck... blah blah blah...





for the SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....SAME AMOUNT OF FUEL.....

for the SAME AMOUNT OF FUEL.....

a restricted intake

is not as efficient

as the non restricted intake.




no matter how much you ramble on to confuse the issue.

bww3588

iTrader: (49)

true, but this has nothing to do with anything automotive or lawnmower or w/e. there is no such thing as the "SAME AMOUNT OF FUEL" so saying its more or less efficient is completly pointless. who gives a **** how many times the air has to turn around before it gets to the engine where it meets the fuel. what matters is what goes on inside the engine, where the fuel flow is constantly being changed to compensate for air flow.

yea, its not as efficient as lets say a FIPK or FTRA, in terms of power, but when it comes to economy, these things are totally irrelevant. different intake setups do NOTHING for economy.

Texfinn

iTrader: (39)

LSx related?