worf928

Subject says it all.

I've got a client's Mass-Air Sensor, rebuilt by Injection Labs with this - shown below - weird 'propeller' thing in it. A forwarded e-mail from Kevin at IL, calls it a 'Tornado.'

Anybody seen one of these before? Is it good? Bad? No data? The e-mail from Kevin suggests that it has a significant effect on calibration.

Mark Anderson

I tried a similar experiment in the exhaust and successfully lost 50hp

hacker-pschorr

I've seen the infomercial for them..... interesting to see Kevin now including them.

Almost every late model car I've seen has some kind of difuser before the sensor wire.
Our Jaguar has a jet engine looking tip with four "blades" behind it. Most other cars have some kind of grid or honeycomb diffuser installed on the inlet of the MAF.

So there's definitely some proven benefit to make sure a consistent even flow of air is going over the wire.

The Murf928 kits started to include a honeycomb screen years ago. We were able to prove a consistent difference between running with and without it. But that is with a 90 degree elbow directly before the MAF. Such a configuration the air is riding the outer radius of the pipe.
However, we never saw a noticeable difference running the same screen on a stock 928, we concluded the design of the air filter box was already doing the job of diffusing the air being sucked into the engine.

It's interesting he's using that device and not something closer to what most manufacturers install.

worf928

I wasn't clear enough.

Based upon the forwarded e-mail, this unit arrived at Kevin's with the 'Tornado' installed in it. It was 'installed' by a PO of my client's GT. Kevin did his testing with and without the Tornado, but the final calibration was done with it installed.

I'm trying to figure out if I need to pull it out and have it re-re-built or if it is good-to-go.

worf928

LOL.

GT6ixer

Just to preface what I am about to write, I have a couple of degrees in aerospace engineering and have been flight testing aircraft and studying airflow for my regular job for the past 18 years. These devices are "marketed" to increase fuel mileage by creating a "tornado" of air to help with air fuel mixing. Snake oil. First off, in its position, it is so far upstream of where the fuel gets added that any "spinning" air it creates will not remain spinning as it travels through throttle body, into the plenum chamber then through the individual intakes. One of the goals with ram air intakes is to minimize the loss of dynamic pressure. This device, one, adds blockage via added material in the intake flow path, and two, by attempting to "spin" the airflow it removes energy (i.e. pressure) from the flow. Bad all the way around. Your call, but I'd toss it in the round file if I found one on my car.

And if you don't believe me here is some crack reporting from my old home town news station.

FredR

Dave,

When one sticks a lump of metal inside the MAF like that it is going to create a flow restriction that will directly impact top end go [see Mark's post]. What these devices seek to do is even out the airflow across the cross section of the MAF. The reason for this is because the smart part of the kit is in the circular section where the hot wire sits and as you will invariably know, the resulting output is considered to be proportional to total air flow. Ironically, looking at that thing, if I was to take a guess as to what was happening when such is fitted it looks as though it might block flow through the actual metering section and thus underread the amount of air flowing yet alone the impact as a restriction in the orifice.

If the folks who put it there can prove it improves overall performance by independent airflow measurement all well and good but I would be amazed if it did as it defeats all my training as a chemical engineer [albeit a somewhat decrepit one these days]. What I can say is that having studied the stock plenum configuration I concluded years ago that it was far from optimal as it was too shallow to be effective as a plenum. The intent of the plenum as I can ascertain is to get an even airflow across the filter at a specific design velocity to optimise filtration. What I noted when I tried the K&N filter was a distinct darkening over the MAF aperture suggesting most of the flow was passing through a small part of the filter surface. Thi prompted me to try the EIS system Roger sells and sure enough I felt a subtle increase in performance but the idle was a bit more wobbly or so it seemed. I then tried a honeycomb in the top of the MAF and sure enough the idle became very smooth but it seemed to me the performance was down.

I then acquired my ST2 and noted how the operating point was wobbling around over two or three cells when idling. This suggested to me that at idle the airflow is surprisingly lumpy- I put this down to reversion pulses- managed to improve things a bit by setting the cells covering idle to similar parameters with a bit more advance and left it at that. Bottom line the system is surprisingly fickle and this begs the question as to just how accurate the MAF is under dynamic load conditions. My guess is that the MAF is too responsive and quite possibly picks up localised flow disturbances. Anyone who has experience with first generation flow meters knows that to measure flow accurately the flow has to be stabilised [i.e. no directional disturbances] for something like 20 times the pipe diameter upstream of the meter and 5 diameters downstream of the meter the fluid is flowing through. In the case of the 928 inlet tract it seems we cannot throw enough disturbances in front of and behind the MAF. To make matters worse the flowrate is changing all the time during performance driving, that we get some kind of meaningful measure is doubtless impressive but I am left wondering just how accurate the metering system really is and the only true way to defeat the limitations of the MAF is to use the MAP sensor approach that John added to ST2.

SeanR

I had two of those things stuff in to the intakes on the airbox on my car when I took delivery. Was funny and had kept them around for discussion purposes for a good many years. Guess I tossed them as I can't find them now.

GT6ixer

Off topic but Sean this quote made me laugh because I was just watching Brian Regan talk about Pop-Tarts over the weekend. Lol!

Wisconsin Joe

Is this it? -

https://www.tornadoair.com/learn-more

I'm going to agree with Nate. This is a total con.

I know some of the boosted folks run "air straighteners", which are usually some sort of honeycomb setup (like Hacker mentioned). It simply smooths out the airflow and takes away the 'burbles" that get formed as the air twists and turns in the intake path.
But those remove any turbulence.

This piece of junk adds it. And, as pointed out, adds it too far from the valves to make any difference when the fuel is injected.

Adk46

DR

Hi Super Dave,

I would call Kevin and ask him. It is obvious it needs to be removed, but if he for real tuned the MAF with that thing installed, well, I know I would want him to re-calibrate it, without a doubt,, 100%!!!

See ya soon,

Dave

worf928

Folks, thanks for the thoughtful responses. I didn't want to bias your comments with my own opinions, so my posts were absent of them. Your responses have provided what I was looking for: evidence of a second (and third, fourth) opinion, kinda like when a patient sees two (or more) doctors. This way I can point my client at this thread and say "See, it's not just me that thinks this is a bad idea! Sorry, but yeah, we need to get it re-re-built."

I have half of your degrees in aerospace engineering, with no professional use of my crusty fluid dynamics other than using my knowledge to calibrate my bull$h1+ meter. I was pretty sure this Tornado was BS.

One thing Nate didn't mention is that with the Tornado thingy in the Mass-Air Sensor the curve of voltage vs air mass is almost certain to have a different shape than what the LH expects. Even if by some magic the fluid effects Nate portends weren't a killer, if this MAF were to go into an un-Sharktuned otherwise stock 928 it couldn't possibly be a good input for pulse width calculation in all cells.

If one could live with the expected fluid effects, then a Sharktuner could - probably - be used to deal with my expectation of a non-OE-normal relationship between voltage and calculated load.

Hi, The Original Dave,
Kevin's (forwarded) e-mail was precise on the very large magnitude of the calibration offset this 'device' causes. If you were to put this contraption in a freshly-rebuilt MAF sensor the result would be as if the MAF sensor hadn't been rebuilt.

But, yeah, he may get a call depending upon if the client wants IL or JDS. Kevin's been silent on e-mail on this topic.

John Speake

I am surprised if Kevin calibrated the MAF with that abortion in it. I would have refused.

DR

Now John, don't be like that! Ha Ha!

I know both of you and respect you both, Kevin is good people just like you.....but keeping it real, he must have been sniffing Titanium fumes that day!

Honestly, had Dave posted this one day earlier I would have suspected an AFJ.

Cheers,

Dave