DailyDrive

I have an ODBII computer too, but your method is overly complex, and inaccurate to boot.

First, the MAF is far from an accurate measuring device. Far more inaccurate than most pressure gauges in fact, since you seem to have a problem with them.

Second, what influences the air flow in the intake? In other words, what influences what the MAF sees? RPMs for one, obviously. How exactly do you plan to carry out your test if any time the throttle is open, the vehicle is accelerating, the RPMs changing along with air flow? Acceleration will obviously be different too, unless it's a perfectly level surface. Wind? You didn't think this out, did you?

To perform this with any accuracy, you will need to place a constant load on the engine. You simply can't do that by racing down some road in the neighborhood.

aviator

Actually DD if you think about it Etrnls request makes sense... yes the engine sensors are "inaccurate" but they are what the ECU is using to control the engine, not the "accurate" remote sensors you and others have been discussing.
So bearing that in mind reading/recording the differences in signals sent under stock and modified conditions would be a "reliable" enough measure for our purposes here IMO. After all all we want to do is see true evidence that the mod makes a difference regardless of how much.
On recording MPG over a 3 mo. period it too would provide an accurate enough measurement since most people are creatures of habit and drive the same routes, usually at about the same time of day, seeing the same volume of traffic day to day as they travel to/from work/grocery store and so on. Of course there will be minor differences but over a three month period they will balance themselves out. In any case I defy any member here to regularly meet the Gov't./Mfg. lab tested MPG ratings in any car or truck it simply cannot be done because those numbers were arrived at in controlled "ideal" lab conditions not the real world.

Parker Runner

I find it entertaining that Daily Drive is suggesting that an HVAC gauge is a better measure of change than a controlled Dyno. Heck, I can see tuners everywhere tossing out their Dyno's in favor of an HVAC gauge.

CRafferty

I find it entertaining that he will not let go that he is convinced this very cheap mod does nothing. As it has been said before, most often with this mod (or the ISR, which I guess you've given up fighting because you know it has SOME effect) it is very inexpensive. Does it really matter what you think about this mod? I think the fact that you continue to flame those of us who believe it does something is more ridiculous than you "evidence" to prove your point.
I say do what you want to your truck (as long as it isn't an exhaust fan put on the intake backwards) if it makes you happy. Don't bash others for what they want to do to theirs, and they won't say anything about what you do to yours. And lastly, leave the HVAC tools out of it, they're not mechanics tools.

aviator

crafty are you saying an electric exhaust fan "turbo" does not do anything?!
horrors! of course it does something... it restricts the airflow and reduces performance... lol

sorry I could'nt resist

DD is just looking for some solid empirical evidence to back up the claims that these mods do make a difference.

Godzilla

Not sure why everyone is so damn protective of a hole in the intake of an engine that produces less than 200hp.
There is nothing wrong with using a manometer to measure any pressure differences in the intake system. People commonly use this as an indicator of restricted and or free flowing air. It is a widely used in industry and is used heavily in diesel applications.
It is quite an accurate measure. In addition you will commonly read that the use of a dyno for ~ +/- 10hp is not generally going to provide you with conclusive results due to normal testing error.
I put some links found after a minute of googling. There are also many peer-reviewed engineering articles which cover pressure loss due to filters and etc.
In some of the original dyno numbers on this topic it must be reminded that it was on a supercharged engine, which may also obviously yield different results.
Anything is better than a butt dyno anyways. But I dont care what you say..I know my throttle body spacer makes my truck awesomer...
http://www.acuramdx.org/forums/showt...&postid=421959
http://www.bobistheoilguy.com/airfilter/airtest2.htm
http://dodgeforum.com/forum/3rd-gen-...ir-intake.html
http://autospeed.com/cms/A_111109/printArticle.html

DailyDrive

I'm not bashing anyone for putting in a deck plate. I have one myself in fact, which I put in many moons ago, but have kept closed most of the time. As I was doing some summer maintenance, I found it again, but this time decided to actually test if it can really do anything.

If anything, this discussion helps knowledge transfer - about air flow, pressures, and how an engine works in general. It seems there is a lot of confusion even about the basics.

Next thread title, "Fuel line magnets or adding a table spoon of turpentine to your tank does not increase MPG".

flyfishexpert

This thread is fun!!

DD what is your background? Sorry if this was already explained!

I like your presentation of the facts. It would be interesting to get a hold of digital pressure gauges to perform the test again, showing data comparing with and w/o decplate. 0 vacuum is 0 vacuum.

Peoples arguments relating to aftermarket intakes vs stock are missing a key point, Surface area. Aftermarket intakes incorporate added surface area for filtration. That is a large key. it isn't what happens before the filter, it is what happens at the filter that is key.

As for the debate with ISR, one would have to perform experimentations there too. If remembering back to my college compressible fluid flow class I believe in this case a more turbulent flow would result in larger volumetric flow rate due to the boundary layer is much closer to the walls of the tube. Thus allowing a larger volume of air to travel at the same velocity.

bgmac

Thats too funny!!

My "Tornado" is radder than your TB Spacer!

flyfishexpert

After thinking about this some more, it would be interesting to place the pressure gauge in the elbow near/just before the outlet into the filter chamber. The smaller crossectional area of the elbow may provide more/better data. Think of it as if you were standing in your house with a window open, if you are in the middle of the room, you don't notice the effects of a breeze blowing through the window, but if you are standing in front of the window it is noticeable. The same volume of are is flowing, but because of the increased crossectional area the velocity decreases.

Kiely

I think the so-called "scientific proof" in this thread is a little simplistic.

The straighter and less restrictive the path air has to flow to get into the engine cylinder the best... 5+ decades of drag racing have proven that, it is also a law of fluid dynamics. So when asked...

"...replacing it with a straight tube does not... decrease turbulence. Is there a scientific explanation why it should work? - Daily Driver

The answer is yes... see below:

"Although high velocity of flow will produce turbulence in any pipe, other factors contribute to turbulence. among these are the roughness of the inside of the pipe, obstructions and the number and degree of curvature of bends in the pipe" - Fluid Power Dynamics by R. Keith Mobley

So will this mod alone increse HP? My guess is probably not by much if at all, there are too many other factors involved, (Intake and head design, exhaust back pressure, etc..). My guess is it could give the impression of better throttle response and give a relatively quiet running engine a bit of desired "grunt".

But at the sametime, I would hesitate to take any automotive repair or mod advice from someone who fails to understand the concept of an oil soaked filter (again proven on the track for decades).

"Judging by what I saw when I handled the high flow K&Ns in my hands... they also looked to be very very poor at actually filtering." - Daily Driver

All and all to me this is making a mountain out of a mole hill. It's a cheap mod, if you like it great. If not, nothing lost put the cover back on and don't worry about it.

DailyDrive

Another one that needs something complicated for it to be "scientific".

The answer is no.... see inside your engine compartment.
The resonator is a straight tube, with a tuned chamber on the side, replacing it with another straight tube should not do anything.


The K&N is a cheesecloth filter that you can read a newspaper through. Sure, cheesecloth dabbed in oil is better than just cheesecloth, but it is still much worse than a regular filter.

You can believe anything you want, but don't go around saying the world is flat. Some people like to understand why the change they did works, not just blindly following someone's (sometimes false) advice to improving something.

DailyDrive

The pressure in the elbow will be lower than in the intake chamber. It's cumulative, so it can never be higher upstream than downstream of air flow. Velocity would be higher, yes, but that's a whole another type of measurement.

BigBallsMcFalls

my IQ dropped 20 points by reading this thread.

so full of fail.

techno

Good, you are demonstrating knowledge of the venturi effect and Bernoulli's principle.

You mean it can't be higher than atmospheric pressure... Velocity is not another whole type of measurement. Its is integral to Bernoulli's equations that show pressure differences. You can't work out one without the other in this respect.

By the way, you will be pleased to hear that so far after one tank of fuel without the deckplate mod, I have not had any significant drop in mpg's! Looking good so far
Also, 3 months of mileage records is more than adequate. I already have 30 months worth of data to compare with. And yes, I'm well aware of the effects of winter gas and will not be using data from in and near those times of the year. Hence why I'm going with 3 months from now. Make sense?

TC4RNR

I nominate this thread: THE most useless tech topic of all time. 12 days, 95 replies, not even one clear cut winner, nothing but bunch of "theories".

Teuf

Twaddle

bgmac

Ok, so who wants to present this to mythbusters?
http://community.discovery.com/eve/f...m/f/2991937776

rocket

iTrader: (1)

Perhaps it's the most interesting and debatable tech of all time. Least I think so.

It's goes south when some can't control their emotions or personal opinions.

Many care about whats being discussed here including those that have capped their deck plate mod as previously stated.

It's been called "infamous" for years.

Tacoclimber

What's this "deckplate mod?"