easy mpg increase?

[razr_88]

on the front of the throttle body, there is a screen that supposedly is suposed to swirl the air a little... I was wondering if i ditched it would the less air resisance allow for better flow of air resulting in better mpg, or would the lack of swirl negate the effects of less air resistance?

i know it sounds like i'm beating a dead horse, but i pay almost as much in gas as it takes to travel to work to make that money in the first place. but i love my olds and i just want her to run better. thank you all for answering all of my questions, i gr8tly appreciate it.

[dmanlyr]

The screen is actualy there to smooth out the airflow. You want to avoid turbulance in the intake air stream with a Multi port fuel injected engine.

If you had a carb'd engine then you could install a screen under the carb base to help atomize the fuel, with a performance loss in top end power though. Doesn't work this way with FI though.

How far do you drive to work? I wonder if a block heater would be a good idea to get the engine up to operating temp as fast as possible, IE when the engine is cold you are running on a enriched fuel map in the ECM ?

David

[Alibi]

Nope, don't take the MAF screen off. Also, don't bother with buying one of those turbonator or tornado air intake inserts. Any swirl those create are negated by the presence of the MAF screen.

Basically, your best bet for good fuel economy is a well-maintained, clean engine and proper suspension/decent tires. Thats about it. That and not driving like a maniac helps a bit too

[razr_88]

ok, so, how do i clean out the inside of my engine, i really don't want to have to take the cylinder head off...
just to note this, i have taken off the fuel rail and injectors and cleaned them up, but if you stick your finger in the injector ports a grimy gunk crap comes out....

[Alibi]

Seafoam. Go to autozone and ask or just look for it.

[razr_88]

i don't know what else to do... i can't keep up with the cost of putting gas in my car... ... o and happy mothers day to all you ... mothers... out there.... lol

[razr_88]

I took the screen off my maf yesterday and so far nothing has happened as of problems. i did notice slightly better throttle response, but i haven't been able to determine the gas mileage yet.

[DrJay]

I would put the screen right back in if you didn't destroy it taking it out. There is a small increase in the CFM capability of the TB without it but the downside pretty much negates it. Besides, giving the engine more air will not increase MPG.

Without cracking open the engine there is very little you can do to a *new* engine to increase MPG. For older cars a full tune-up is the one of the best things you can do.

Good read: http://www.fsec.ucf.edu/Pubs/energynotes/en-19.htm

[razr_88]

hey you.... keep an open mind here. if we're going to get through this gas shortage thing, we gotta start doin something about it.

o and as for more air decreaseing mpg, thats a myth. think this through logicaly as you read this. say you have a set amount of fuel, if the is fuel injected in predetermined amounts more oxygen allows the gases to burn more completely and delivering more power. if you drive conservatively less fuel is needed to keep the car going due to the fact that more power is being produced. what you hear about it decreasing mpg, is about people who want to go faster, not improve their mpg, so they accerate hard, brake hard, and thus waste more gas. ok, so i know 2-5 mpg increase doesn't sound like much, but do the math.

18 gallons per tank * 2 mpg increase = 36 right? 36 extra miles to the tank, and say i go through about 20 tanks a year. 720 extra miles. at an average of 25 mpg that's like 28.8 gallons saved. at $3.00 a gallon, that about $86.40 saved.

i can think of a lot things i'd rather spend that $86.40 on than gasoline.

[DrJay]

Not sure if you're referring to me but I didn't have a closed mind at all when I posted that reply. As for the MAF screen, it's important that it stays intact. The purpose of the screen is to make the air laminar before hitting the MAF sensor itself. Without it the turbulent air may make its way around the sensor and result in a lean condition. Most see this happen at idle and report a rough idle as a result. You're far from the first to try it.

I get what you're saying but you're a bit off in your analysis. Lets assume pulling the MAF screen did give you additional airflow. First the MAF sensor will tell the PCM that you're getting additional air and it will then increase the pulse width of the injectors in an effort to maintain stoch. That failing, it will then be caught by the o2 sensor which will do the same. This is how power is increased. Air does not = power. Fuel does not = power. Air + Fuel = power. If you had a way to control the pulse width of the injectors you could do what you're saying and save gas. They do it in racing all the time when they're running low on fuel. It drastically decreases power and risks burning up an engine, but sometimes just finishing is most important. You, however, do not have that capability.

What you'll need to change is the efficiency of the engine, not necessarily the power produced. Better efficiency will generally yield better power, but it doesn't always work the other way around especially in the way you're describing.

One big thing to keep in mind was mentioned above. Air + fuel = power. Since the PCM will command the same ratio no matter what power you're making, simply adding airflow will ALWAYS cost you more fuel, even if you keep your foot out of it. The only difference is you may be making the required power without your foot being as deep into it !BUT! if you do nothing for the efficiency of the engine, the power required to maintain 60mph will ALWAYS require the same amount of fuel and air. No matter if you make it with the foot to the ground or barely tapping it. The only way you can keep your foot out of it and still maintain 60mph is to change the gear ratio or tire size. This is why the Overdrive feature was added.

Hope it all makes sense.

[acidcrashdburnd]

can having bad struts cause bad mpg just wondering i have 4 new struts for my car i jsut have to put them in car kinda bounced errrmmmm every where hit a bump bounce down the road untill i stoped lol its pretty bad gives me and my friends something to laugh at

[dmanlyr]

Well, I would imagine that there would be a slight increase in fuel usage at say a fixed hiway speed as it would tend to interupt the airflow and also the bouncing could raise the car and therefore pack more air under it which would cause more drag on the rough undersides. ??

In the same line, Raz - If you were to lower your car, along with adding a large front airdam that has some aerodynamics you should see a increase in MPG. Same thing with having a window down / open that will decrease your MPG. Sure is not fun though to drive around in a car with no a/c and the insode temp at 140 degrees with the windows up!

Just more thoughts on easy ways to increase mileage.

[razr_88]

hey i thought that gm made that learning thing with the brainbox din't they? doesn't it like control the pulsewidth from the sensor inputs?

if not, then could i somehow change the pulse width?

[razr_88]

here are some good links that may proove my point that a cold air intake does infact increase fuel economy

http://www.usdieselparts.com/pages.cfm?ID=117
http://www.knfilters.com/feedback13.htm
http://www.autoanything.com/air-intakes/50A5A115A1.aspx
http://www.aa1car.com/library/gas805.htm
http://www.wikihow.com/Save-Gas

[dmanlyr]

Which is why your CAME FROM THE FACTORYwith a cold air intake. But not as a fuel MPG improver, but mainly as a performance enhancer.

A aftermarket LARGER cold air intake wil not improve your fuel mileage on a stock engine though. REGUARDLESS of the "advertising" claims. This has been proved many times over.

But - it does open up the intake tract and makes the engine sound better if you like that sort of thing - and doesn't a louder engine make more horsepower simply as a function of making more noise? NOT!

As to real increased horsepower with a aftermarket Cold air intake... NOT at your normal cruising speeds. You may gain a slight increase in horespower at high rpm, but then running your engine at those higher speeds kills your fuel mileage.

D