this makes sense to me... i doubt if i tried it on my car i would see any difference but i guess its one of those things you scratch your head about if its working on your car thats great

 

Agreed again, but if you let the tailgate down in the truck the leaves blow out and your gas mileage goes up 1-2 mpg! The air deflects off your elbo but if you flip our hand up there is a strong drag. That being said I have read numerous articles over the years that questioned the benefit of any of the factory OAI set ups for the same reasons you just stated. There is a negative airflow under 1-2 inches above the hood.

 

You want to really gain some MPG?
Mix 3oz of Acetone with 10gl of gas a few times.

 

Wanna bet?

Mythbusters Database

Once again, this is why I continually say that subsonic aerodynamics and airflow is NOT intuitive. The flow lines rarely travel the way you think they will. Supersonic aerodynamics are different and much easier to calculate, as I learned with the dinosaurs when I was in college.

 

Well I learn something new every day.....I stand corrected.

 

Yeah, I also heard that back in the 80's. I drove my truck, 79 regular cab 8' box 4 wheel drive, on a 200 mile 1 way trip with the tailgate down. On the return trip I left it up. NO difference in mileage.

 

If you were living up here in the "great white north" where gas is about $7 a gallon for regular, if someone said they could squeeze another yard out of a tank, you'd probably try it !!

 

what he said

 

I'm sorry, but Bull Sheet. If you cared that much about the cost of gas, you'd be driving a Prius.

 

Please don't consider Mythbusters to be science, or their results to have any scientific weight about them. They are the technical counterpart to snopes.

I was using the pickup truck as an example of boundary layers, and shouldn't have mentioned it, because it's Something Everyone Knows, like it's in the man code or something.

To redirect back to topic, there will be no noticeable drag reduction when plugging the hood.

 

My friend,
You're sharp as attack this morning.

 

Badda BING...

 

Well I for one am certainly glad that Padavano and queer picture guy cleared this up. There is no way this could have worked because they, in their infinite wisdom of the hypothetical, have determined exactly that.

 

Drove up to Alliance for the Olds show today . 320 mile round trip . 115 miles of the drive up no foam, cool morning , windows up ,60 - 65 MPH (11.8 MPG ) Put foam in and drove another 205 miles ,coming home 85 degrees, windows down, vent windows open, 60 -65 MPH. (16.9 MPG) Also the long distance award and best of shoe went to a beautiful red W-30 with 00000.5 miles on the odometer . Gotta love the trailer queens

 

That could not have happened.

 

I agree a car like that shouldnt win anything....a half of mile? That poor car never been driven....i thunk if it had to put any more miles than just backing off the trailer the car might just implode into a dust pile

 

Au contraire!

Mechanical odometer - it backs out of the trailer, then drives onto the trailer.

Backs off, drives on.

Backs off, drives on.

The car could have 100,000 miles on it, all just backing up and driving forward, constantly canceling the mileage it just put on.

- Eric

 

Very clever

 

Honestly, though, if a guy restored a car and installed a 00000.0 speedo, and all he ever did was trailer it to shows and back it off, since most of his driving would be the same distance in each direction, with the occasional insane, breakneck 5mph drive down a row to get to his space, he could do that for years and rack up only a small fraction of the actual (tiny) number of miles he had put on it.

That being said, I wouldn't be surprised at a trailer queen jockey getting under the car and turning back the odometer after every show - how hard would it be?

- Eric

 

Eric, you're cracking me up. Wax on, wax off. How about if the trailer queen just took the speed cable out of its housing? Voila! No mileage at all.

The car could have 100,000 miles on it, all just backing up and driving forward, constantly canceling the mileage it just put on.

LOL!^^^

 

No way would he diss the speedo cable ...thats the first thing a judge is going to look at on a half mile car

 

That's.....the best you can do? "Queer picture guy?" Lawlz.

Let me see if I can think up a retort........oooh, oooh, I GOT ONE.

Ahem, cough, ahem. "THAT'S NOT WHAT YOUR WIFE SAYS!!!!"

Can we come back from the third grade now?

 

I'll give you the benefit of doubt that you're measuring miles and fuel accurately, which may be generous. Different gas pumps shut off at different times.

All I can say is that running with the scoops open must be making your carb run really rich at cruise, or running with them plugged must be making the carb run really lean. And, as a certified ASE Master Tech, you should be capable of determining which it is and adjust the carb accordingly. Let us know what you determine.

I've considered making similar scoop plugs because 1) I'd like to measure the effect of OAI/no-OAI at the dragstrip, and 2) I've always wondered if the scoops might lead to higher underhood pressures, thus making the cooling system less efficient. I've wanted to experiment with this with some pressure sensors. Some day ......

 

a 2100 mile trip with a rats nest in my air cleaner (unknown to me) produced 39mpg in my dodge neon!! Remove nest and replace air filter 25mpg. Can't get more scientific then that

 

Yes, and in the true spirit of science, it's an experiment with no relation to the subject at hand.

The Neon is a computer-controlled, closed-loop, fuel injected car with a mass airflow sensor.
The sensor senses how much air is being drawn in, adjusts the fuel delivery for proper ratio, taking into consideration the throttle position, and adjusts the ratio based on the O2 sensor reading of the exhaust, so a blocked air cleaner will simply reduce maximum airflow, keeping the A/F ratio correct.
Essentially, it's the same as putting a block of wood under your gas pedal.

It's a very different story in a carbureted car, where reducing airflow will inevitably richen the mixture, potentially causing poor running and reducing fuel economy.

We still don't know what factor caused the improvement in fuel economy in Tom's Vista (if in fact there was an improvement), but whatever it was, it was not simply blocking intake airflow.

- Eric

 

Please do everyone here a favor and stop the argument at the same time. Put a regular open element air cleaner on it and check the mileage. Ram air or no air what will happen?