Mitsubishi Karman Vortex Air Flow Meters: How they really work

heres why pod filters are a waste of time..

Many thanks to Kenneth on ClubVR4: http://www.clubvr4.com/forum/showthread.php?t=27073

 

That's why when people go a full aftermarket system they change the sensors.

 

So how come your intake mod works then, Carsten? I know you were having problems when you had a standard pod, but once you moved it into your cold air box, everything's gone back to being good. Care to elaborate?

 

i have a stright bit of pipe before the maf with the cold air box setup...
strightens out the air enough to make it readible by the maf...

when i had the pod directly on the MAF it just ran like shit,
lacked power and boost cut at 9psi....

its still not perfect thou... i still have over-fuelling, (280km to a 55L tank of 98octane gas)
but i put that down to all the mods i have,

i just need to tune my MapEcu and it should all be good,
and since i will be running MAP instead i can ditch the MAF all together

AFAIK there is no aftermarket AFM you can use on the mitsi's
(thats a direct plug in with no other bits needed)

only way to sort it is get an ecu to tune it out,

 

Hmm sounds like its not worth screwing with intake unless you have a replacement or piggyback ECU to go in at the time, then...

 

The theory of this is correct but Pods do work on these units. But only the RIGHT type of pods. For many many years we (RPW) have been advocating the K&N Oval shaped pods which were origonally designed on the Mitsubishi 3000GT vehicles. These are not round, and the adapter is designed to actually funnel the air into the MAF unit, without disrupting the air flow characheristics. Basically because its oval shaped, it doesn't create a "Swirling Action" of the air and as such, the air is smoothed out and driven into the MAF Unit.

I lost count a long long long time ago of the number of customers who have fitted a "Universal" pod filter to the Mitsubishi MAF untis, and have them running badly, running rich or idling bad. They then fit the K&N Oval shaped unit, and it runs better and makes more power, without being in a restrictive air box.

I can say catagorically, that the unit we are marketing and sell (We sell at least 5 of these a week minimum) will definitly create more power and throttle response without ANY side effects.

Feel free to come and take me up on this as I garauntee it won't cause a problem

 

Longer pipe between air filter and MAF and cold air box sucking air from outside will do the trick, imho...



A good read over here:

http://www.msport.co.nz/viewtopic.php?t=2413

 

Actually your wrong again. The oval shaped I am referring to is the shape of the air cleaner the K&N unit. The same adapater goes across to every single Mitsubishi MAF sensor model ni the whole range. The section of the MAF unit which lets teh air pass through, is usually two square shaped units. Its the shape of the adapter going onto the MAF and teh air cleaner itself which is what matters.

Having fitted so many of these to so many different model Mitsubishi units from EVO, Magna, lancer, galant, FTO, 3000GT I see the same result time after time.

The shape of the MAF unit after the entry point of the air doesn't matter. It all comes down to the air being drawn into the air filter chamber and shaped and directed into the air flow meter.

When you see these kits it makes a lot more sense

 

Dave, surely isolating (through the use of piping and a cold air box) the air being drawn in through the filter is beneficial as it will be colder? Just sticking a pod filter on before the MAF sensor means the air you're sucking in will be quite hot to start with, right?

 

hmmm interesting subject.. i have a blitz pod suited to my car and i have no problems with ideling and/or over fueling.. i get round 450-480 city km's i only have a 3"cat back zorst, pod, wheels and coil overs.. stock boost..

 

I made a mistake and corrected my initial post. True - they are all oval on the intake of the MAF, so it must be beneficial to all makes and models of Mitsubishi. I've forgotten how the stock MAF looks like... sorry.

However, straighting the air flow with a longer intake tube does seem to take care of the problem with "dropping counts" by the stock MAF. And placing a Cold Air Box helps further, by getting colder/denser air from outside rather than sucking up hot under hood air.

 

Correct that just putting the pod straight in the engine bay negates some of its benefits. I think of it this way the say 50% air flow improvement gain is negated by 35% due to the hot air. But if your asking me whether I would still do it - definitly because at the end of the day - thats what the intercooler is there for to cool the air down so the increased air temp becomes a minor problem at best. Not like a N/A car where it doesn't have the option of cooling the air down in the first place.

Extending the pipe after the MAF unit does seem to produce similiar results from what I have seen, although I have always located the MAF / Pod Filter at teh end of extended tubing myself.

I have seen some cars run properly with other brand filters, and A LOT that run badly. I beleive it comes down to how well in tune your car is to start with. If it is already slightly lean on the tune, then a slightly richer result probably doesn't harm it or the kit is within the tolerance range of the closed loop oxygen sensor control ability to correct maybe.

For myself, I have just stuck with the filter package that I KNOW works each and every time. And for me thats the part that matters, being able to sell a product which I know 100% is going to work without problems. Plus due to the volume of these we sell, they are not that expensive.

 

Ok, an opinion question, then: If you were going to run some straight tubing into a front oriented cool-air box, what would be the BEST air filter to use? A standard pod, an oval pod? Some particularly fancy high-flow filter? Personally I'd like to get the benefits of both high-flow AND cold-as-possible intake air, and a straight pipe coming from a cold-air box seems to be the best solution for that.

Thoughts?

 

When writing that post (I don't recall Gly asked my permission before copying it though... I would have prefered it be linked rather than copied) I was aware of the K&N oval filter, however their use doesn't seem to be wide-spread (at least in NZ and the UK) and I didn't really want to add another level of complexity to the whole thing.
EDIT: And I didn't have any proof other than what K&N say, and I never endorse manufacturers claims without proof. I am happy to take your endorsement though and will add it to the original post.

Unfortunately I have found that if the information is too detailed and technical, most of the readers don't understand it well enough to find it beneficial. Make it simple enough for most and then the more technically minded pick it apart for not being complete. Hard to win really.

To anyone who does read this, I would recommend that if you do wish to get a pod filter, ensure you get the one as shown in post 8 (http://ozvr4.com/forums/showpost.php?p=11061&postcount=8)

If you don't wish to spend the money, I would cut a hole in the bottom of the snorkel and pipe fresh air into it (3" will do) from lower in the car.

The standard airbox and intake system was good for over 180KW at the wheels on my car. Only intake mods were a Ralliart panel filter (this filter is DRY, so no oil) and a 600x300x76 Intercooler. This system being less than ideal, I can see more room for improvement in other areas than ferking around with the filter and air box. Again, my suggestion would be to pipe cold air into a hole cut in the bottom of the snorkel. Don't forget the air box opening is larger than the MAF opening and isn't going to give any flow restriction worth mentioning.

 

I'm running a Blitz Sonic Pod and I don't have any issues with boost or idle. But I will be doing some AFR testing with Silicon Angel with a standard box soon as we get some time (using Logworks3 and Evoscan). I'll be posing the results up on here soon. I'd like to try a few different pods in the future.

 

I have updated the original post: http://www.clubvr4.com/forum/showthread.php?t=27073

Could a mod please link to this in the original post please?

 

To be honest, with pod filters it can be a bit hit and miss, though mostly miss. Most don't work, though occasionally there is someone who doesn't have any issues whatsoever.

I think a large contributing factor is the pod adaptor, with the correct one you probably get a much better air flow. After looking at a few I get the feeling that most just don't have a wide enough opening which interferes with the air flow into the MAF.

It would be interesting to see what % of airflow frequency difference over standard there is with different pods AND different pod adaptors.

 

Done.

cheers

Lee

 

*Crosses Lee off his list*
(Think Psycho played by Steve Buscemi in Billy Madison)

 

LOL!