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VR4Kaos
10-06-2010, 08:28 AM
as some may knoiw i got a hks pod mushroom filter that is highly hated by fellow members well im finaly looking to replace it thinking of this
http://cgi.ebay.co.uk/Mitsubishi-Evo-Blitz-Sonic-Air-Filter-/330439508370?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4cefbac192
is this any good if not can one be recomended or even twin ?
want to sort this issue before eurospec RR day init

Wodjno
10-06-2010, 08:35 AM
That will just gave same effect as an unshielded mushroom filter.. Your best bet would be to get hold of a standard airbox and updated panel filter for now.. And then if u want to, you can then look at moving battery to boot(or turn it sideways) And making ajnew air box and intake there.

PaddyB
10-06-2010, 08:38 AM
You'll still be sucking in hot air => bad (unless you've got a cold air feed).
Accepted wisdom is the std airbox can't be beaten (unless you've got a cold air feed).

btw. I have one spare (actually 2) - £20 & it's yours ;)
I have a panel filter too that I'll throw in for that price but I've no idea if it's any good.

VR4Kaos
10-06-2010, 08:40 AM
You'll still be sucking in hot air => bad (unless you've got a cold air feed).
Accepted wisdom is the std airbox can't be beaten (unless you've got a cold air feed).

btw. I have one spare (actually 2) - £20 & it's yours ;)
ill have it off ya mate asap only need box already got scoop

Gowf
10-06-2010, 10:00 AM
Just out of curiousity. Has anyone actualy got any true impartial scientific proof for the 'shroom filter being pants other than hearsay and conjecture?

Has anyone had their car on the dyno with stock air box, then with 'shroom?

Id be interested to know, as clearly from stock my engine must have been far exceeding the factory power!

Wodjno
10-06-2010, 10:01 AM
I would advise getting one of these also ...

http://cgi.ebay.co.uk/HKS-REPLACEMENT-PANEL-FILTER-MITSUBISHI-GALANT-/270588907361?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3f005b0f61

Or a Piper cross or K& N Compatible etc

John TheAntique
10-06-2010, 10:19 AM
I've got a Blitz sonic ( you can make it whistle ) and it doesn't seem to make any marked difference.

John TheAntique
10-06-2010, 10:29 AM
Found it

bradc
10-06-2010, 10:32 AM
We've had multiple dyno results in NZ with pods that have shown a reduction in power and a richening of fuel maps.

Gowf
10-06-2010, 11:52 AM
ok, thats not what i asked brad. Do you have results from the same car on the same day, at the same time of day, on the same dyno, with nothing changed but the air filter?

Wodjno
10-06-2010, 11:56 AM
ok, thats not what i asked brad. Do you have results from the same car on the same day, at the same time of day, on the same dyno, with nothing changed but the air filter?

Well theres a RR Day not to far away.. So let's get the Raw Data on the day..
Sure there'll be someone with a Mushrrom there on the day that can do a swap over /yes
Or we can sort 1 out :upsidedow

Turbo_Steve
10-06-2010, 12:30 PM
Gowf -

Nothing quite that imperical, however several people who have had issues with fuel cut have removed the pod and gone back to a panel to find the issue resolved.

I've also seen mine use significantly more fuel over several months with a pod than with a box, doing the same journey day-in day-out.

Once you're into ECU territory, it stops being an issue as you're modifying the maps to suit the stuff you've got fitted, but if you're on the standard MAF and ECU there seem to be some issues with accuracy.

And, as I keep on saying over and over, it's got feck all to do with hot air. :D

AlanDITD
10-06-2010, 01:31 PM
yeah can someone cant do it at eurospec on the day...or even a few cars do it as one may be differnt to another.

All the hear say around this just gets on my nerves...no one knows **** as far as im concerned when it comes to pods and panels and standard boxes and power gains and power losses....not one person that claims a power loss can back this up scientifically!

The position of the pod will be vary the results possibly...pedro was mean to send me my old pipe work if he could send it to a member thats going to the RR day they can use that. Im convincied it works well but would be interested to see the dyno results!

So pppppppppleeease someone do it to settle it either way.

Gowf
10-06-2010, 01:51 PM
yeah can someone cant do it at eurospec on the day...or even a few cars do it as one may be differnt to another.

All the hear say around this just gets on my nerves...no one knows **** as far as im concerned when it comes to pods and panels and standard boxes and power gains and power losses....not one person that claims a power loss can back this up scientifically!

The position of the pod will be vary the results possibly...pedro was mean to send me my old pipe work if he could send it to a member thats going to the RR day they can use that. Im convincied it works well but would be interested to see the dyno results!

So pppppppppleeease someone do it to settle it either way.


This is my point exactly. There has been far too much chat about it, but no true data aquisition in any form of impartial way.

I know there has been indepth talk about disruption to the air flow causing indiscrepencies in the vorticies that are then created, but it does need some form of results to prove the theory. I fully agree with you though steve on the hot air front, as surely you would fuel less if it was heating the air significantly?

But my point is, was mine the only success story of a 6a13tt with one? And out of curiousity, if its creating more issues with fuel cut, is that not down to it flowing more air?

Wodjno
10-06-2010, 01:55 PM
Don't even need to go as far as swapping over to a pod or shroom filter /Hmmm

I'm sure if we just took off the snorkel and front part of airbus off it would give pretty much the same results.. Filter should stay where it is as its being sucked not blown :D But a bit of Gaffer tape will hold it secure while not on throttle.. /yes

Gowf
10-06-2010, 02:12 PM
Yeah but as its a different shape to the mushroom filter it will have an influence on the flow as it hits the maf, which is the basis of the arguement, so would be best to swap

Turbo_Steve
10-06-2010, 02:47 PM
I agree there is nothing empirical, but I think there is enough anecdotal to know that the reading is different: if the pod actually allowed more flow, it would surely manifest itself as higher boost, no? People running the exact same boost target are seeing fuel cut with a pod, and none without.


I am not disputing that it may not make a significant difference in the midrange, but it absolutely categorically changes the load point approaching fuel cut.

Mine didn't feel any different at all going from one to the other (Pod > Box)...so much so that I was dissapointed. However the cars overall fuel economy was improved by 2mpg (increased to 17mpg from 15mpg. Epic.). What that only proves is that MY filter was a problem.....maybe it was dirty.

I'd be very interested to see someone do a couple of runs with Evo scan, if they've got it?

I'd be even more interested to see what some pipework will do, as positively pressurising the airbox is always a big win.

Gowf
10-06-2010, 03:07 PM
I am agreeing with all this as there are sound arguements for it. But the extra air flow going through the maf at certain engine speeds are what cause the fuel cut no? Surely in upping the boost it is sucking more in through the maf, and thus this air flow is out of the region it want to see. By that logic if a pod is causing fuel cut then surely it is allowing comparitively more flow. And yes, unfortunatley more flow does mean more fuel, so for the same values you would be using more. So i do agree that it may be detrimental in some respects, but as an outright better filter then yes it could be, but as you say, as it will have changed the VE then you should map accordingly to get the most out of it

VR4Kaos
10-06-2010, 04:00 PM
swapped back from mushroom filter to original stock air box and omg what a differnce in excelleration responce its huge ! thank you Paddyb rep is on its way to you mate for supplying and fitting the niggly thing lol

Turbo_Steve
10-06-2010, 05:53 PM
But the extra air flow going through the maf at certain engine speeds are what cause the fuel cut no?

That's the bone of contention, right there: users running specific boost change filters, get the same boost but do/don't get fuel cut.

I believe these filters can offer a significant performance increase: unfortunately I believe you need to remap to take advantage of it.

I guess the most concrete proof would be to find a way of measuring the flow through the MAF sensor on a bench, then try a cone filter, and then a cone filter with a stabilising mechanism.

The primary cause of the issue seems to be that most MAF adaptors actually funnel the airflow towards the centre of the MAF. As this is a "tuned pipe", this effectively increases the airspeed by reducing the diameter, causing it to over-read.

Again, I have no proof at all, but if you look at the MAF, and an adaptor, it starts to become clear.

I suppose the best thing to try would be to drill a hole in a V6-24 airbox and fit a pod to it and chuck a baffle inside, then fit the whole caboodle to a VR4 and see what happens: the baffle / box arrangement should mean it sees normal airflow but without the restriction of the MAF adaptor OR factory airbox?

bradc
10-06-2010, 08:05 PM
FFS, Yes Gareth. Candee had his car on the dyno within 5 minutes with the two setups.


Pods suck arse, just fvcking listen to us that have done testing and deal with it rather than all of this bullsh1t whinging that a few of you continue to do regarding this issue.

bakerboy-2007
10-06-2010, 08:58 PM
I've got a Blitz sonic ( you can make it whistle ) and it doesn't seem to make any marked difference.
How do ya make it whistle?

Wodjno
10-06-2010, 09:01 PM
FFS, Yes Gareth. Candee had his car on the dyno within 5 minutes with the two setups.


Pods suck arse, just fvcking listen to us that have done testing and deal with it rather than all of this bullsh1t whinging that a few of you continue to do regarding this issue.

/popcorn

Turbo_Steve
10-06-2010, 09:06 PM
Brad, if you've got these results, post 'em up.

And did you try the pod filter with a stabiliser pipe, or straight onto the MAF.



Pods suck arse
Frankly, brad, so did your last post.

I appreciate you're frustrated, but that kind of rudeness is totally unnacceptable.

Wodjno
10-06-2010, 09:10 PM
I would be interested just to see if there is an Air Intake Temp difference /yes

Cos think, believe it or not that it has got "Feckin Summat to do with HOT AIR" :p

VR4Kaos
10-06-2010, 09:16 PM
well i had the stock snorkle 2.5" away from the mushroom but there was still a lot of area to suck hot air into maf in fact probly helped circulate the hot air better imo for what its werth

bradc
10-06-2010, 09:21 PM
I don't have the thread handy, but send a pm to Candee and he will dig it up for you.

Wodjno
10-06-2010, 09:29 PM
I don't have the thread handy, but send a pm to Candee and he will dig it up for you.

Search is your friend /Devil5

http://www.clubvr4.com/forum/showthread.php?t=37871

/popcorn

swinks
10-06-2010, 09:38 PM
Garreth and others!
You wouldn't argue so much if you knew that my point of being in next RR is exactly comparison panel filter with induction filter on dyno.
If you read threads carefully you would know, that soon mystery of performance different filters in same car will be solved. /woot
So, it's HKS panel filter vs. BMC CDA-150 forced induction. Hope since then we will have at least a bit scientific argument which one is better, not a Harry Hill style ;)

Turbo_Steve
10-06-2010, 09:50 PM
It's negligable. It really is. It makes a very very small difference on a dyno (because they don't work like driving on the road).


The airflow through the front grille of the car is measured in 1000's ft/s at 10mph. The heat transfer at that rate of flow is huge - the raise in air temps under the bonnet is less than 1 degree once you're moving on most cars.

The airflow through the filter is going to be a maximum of 800cfm unless you have some truly epic mods (Gowf spec or higher).
So by the time you've breathed in 800cf of air, the engine bay has exchanged around 100 times that much. This means your inlet breathes hot air for around 0.5seconds...and at the point where it's not on boost yet. I've run several cars with temp sensors in the inlet tract, and the only time it all heats up is standing in traffic on a hot day. As soon as you're moving, the temps start to drop. The main culprit is the heat soaking into the pipework, and heating the air on it's way through - not the induction.

If hot air was a problem, Racing cars would go to more effort than they do.

To give another example, I've tried both external inlets and underbonnet pod filters for drag cars. It made no difference at all to the drag time, and only a marginal difference to the inlet temps whilst standing on the line revving the pants off it. As soon as it was moving forward, the temps hit ambient.



Swinks - The BMC CDA is likely to be more restrictive than the factory airbox - look at the pipe sizes.
It's not a fair test unless you try several filters.
It's also not a particularly fair test unless you run it with the bonnet up and several VERY large fans.

swinks
10-06-2010, 10:00 PM
Steve, not with my mods to BMC. Intake same as panel filter, output is 4.5".
See the picture: http://i278.photobucket.com/albums/kk120/swinks_UK/Misiu%20Galant/th_P1040666.jpg (http://s278.photobucket.com/albums/kk120/swinks_UK/Misiu%20Galant/?action=view&current=P1040666.jpg)

Turbo_Steve
10-06-2010, 10:31 PM
Well, with your mods I dunno :)

But normally they are rated at 430cfm or so....which will limit peak power.

wintertidenz
10-06-2010, 11:17 PM
I did a run with Evoscan on the street with my pod in the car. I'll see if I can dig up the thread later on... I will also be reverting to a stock airbox soon so will also do Evoscan runs after 200km of allowing the car to settle and measure the difference.

I suspect that the dyno figures could be skewed by pulling the air box straight off and fitting a pod... the car DOES need time to adjust the ECU to the new airflow etc, so doing an immediate swap doesn't help things.

carbonvr4
10-06-2010, 11:28 PM
Hi guys, i live in Adelaide Australia, and the word also over here is that you are better off with the original air box, dyno data is proof of that, disrupts air flow
Im looking also for tho original box i have the air intake, does anyone have a spare to sell, ill pay good $$$$$$ for it.

elnevio
10-06-2010, 11:29 PM
I did a run with Evoscan on the street with my pod in the car. I'll see if I can dig up the thread later on... I will also be reverting to a stock airbox soon so will also do Evoscan runs after 200km of allowing the car to settle and measure the difference.

I suspect that the dyno figures could be skewed by pulling the air box straight off and fitting a pod... the car DOES need time to adjust the ECU to the new airflow etc, so doing an immediate swap doesn't help things.
Reset the ECU before BOTH runs?

wintertidenz
10-06-2010, 11:39 PM
Nev - yes that's possible, car would run rich as hell on the dyno while it relearns though.

VR457
11-06-2010, 12:03 AM
I would be interested to see if the air intake mod i fitted makes a difference on the dyno. Need to be able to afford the £100 or so a round trip to Guildford will cost. Can i get two dyno runs on the day for that?

Turbo_Steve
11-06-2010, 12:16 AM
he car DOES need time to adjust the ECU to the new airflow etc

Actually, no it doesn't - MAF scaling is fixed: the ECU has no basis for comparison. That's actually pretty much why we have the problem - if it DID have a closed loop mechanism for MAF compensation, it would learn it's way around a pod filter.


Hi guys, i live in Adelaide Australia, and the word also over here is that you are better off with the original air box, dyno data is proof of that, disrupts air flow

Okay, yes, we've seen that some (if not most) pod filters cause issues on the Standard ECU when bolted directly up to the MAF.
But the debate here is whether an alternative arrangement with a pod filter will allow better flow than the factory airbox (which is a fairly compromised design).

AlanDITD
11-06-2010, 12:18 AM
i give up, Chinese whispers have taken over. Scientific rational has left the building....

VR457
11-06-2010, 12:25 AM
i give up, Chinese whispers have taken over. Scientific rational has left the building....

You need an e

VR4Kaos
11-06-2010, 12:54 AM
I would be interested to see if the air intake mod i fitted makes a difference on the dyno. Need to be able to afford the £100 or so a round trip to Guildford will cost. Can i get two dyno runs on the day for that?
are you comin ?

VR457
11-06-2010, 01:09 AM
Will try my best. Need to know my AFR's. Blown bank account not helping anything at the mo. Dont play lottery neither!

crazyken76
11-06-2010, 01:17 AM
i would just buy your self a pannel filter i put a hks mushroom filter on mine and i lost loads of power and the fuel cost went up as well

VR4Kaos
11-06-2010, 01:25 AM
hope ya can make it J it will defo be a good day

Kenneth
11-06-2010, 06:41 AM
Why is the factory airbox a compromised design?

The air inlet of the factory airbox is in a high pressure zone and the intake area is larger (by a significant amount) than the MAF intake.

I have had no trouble with the standard airbox up to just shy of 200KW at the wheels (standard ECU, no tuning, piggy back etc). I have NEVER seen a car with a pod filter arrangement get close to that figure while still using the standard MAF, the most I have seen is just shy of 170KW.

Our dyno days are done with the hood lifted and a HUGE fan feeding air towards the car. The intake temp is going to be negligible, at least as much as driving will.

When someone can show me a pod arrangement that, on a car which has no compensation (i.e. tuning, piggy back, no maf etc) and can exceed 200KW at the wheels, ill agree that you can do as well with a pod.

Good luck!

Turbo_Steve
11-06-2010, 07:44 AM
Why is the factory airbox a compromised design?

Easy enough to answer - you need a PC fan and a lit cigarette. Try it and see what I mean! It's designed to be a resonant chamber - I'd imagine to surpress induction noise. As such, it stagnates massively at lower flow rates.
So whilst it's not affecting peak power one bit, it's definitely not helping throttle response and spool. I'd be the first to accept that these aren't a "big deal" however they do seriously affect driveability. That "boggy" feeling you get with a pod filter in the engine bay when in traffic is a similar analogy.


When someone can show me a pod arrangement that, on a car which has no compensation (i.e. tuning, piggy back, no maf etc) and can exceed 200KW at the wheels, ill agree that you can do as well with a pod.

Which takes us back to where we started :D

Kenneth
11-06-2010, 07:48 AM
I disagree with the theory on resonance sorry. (unless you use a different word for the same thing as I am thinking, which has happened before... lol)

I would say it is more to do with creating a slower moving mass of air so that the MAF gets a stable vacuum to draw upon, which in turn ensures the correct reading.

The GDI I had used a resonant chamber, it was pretty funny without it actually.

Ok, so I have a PC fan and a lit cigarette... what then?

bradc
11-06-2010, 08:25 AM
I'm out of this thread too as I've been given a warning with two points for saying that pod filters are bad, even though I'm the only one in the thread to make specific mention of a thread (thanks wodj for finding the link) where there is proof. It sounds like swinks is on track to test and find out the difference as well. I can't wait to see the results. Thank god someone else is actually doing testing rather than just being a keyboard warrior that doesn't know what they are talking about, or just 'thinks' they know something.

To the rest of you running pods or refusing to listen, go and run your pods. I don't give a crap. Enjoy your wasted fuel and less power.

Sure one of you may be lucky enough to engineer a solution that will nearly as good as stock, but most people won't be anywhere near lucky enough.

Candee makes specific mention of the results here http://www.clubvr4.com/forum/showthread.php?t=45287&page=2&highlight=pod I can't find the graph though.

chris g
11-06-2010, 08:40 AM
Brad, you may not believe this but, well said...

I agree with your sentiments

If you want to have a pod/mushroom filter, whatever, have one

If you like it, good for you

Experience of owners shows not so good for the std VR-4

This is like AMSOIL, take the advice, don't take the advice

It's up to you...

Nutter_John
11-06-2010, 11:07 AM
I'm out of this thread too as I've been given a warning with two points for saying that pod filters are bad,

No Brad you have not been given two points for saying that pod filters are bad , it's the way you said it !!!

bradc
11-06-2010, 12:15 PM
Yep, because no one would listen to me. As I said above, people can run pod filters, I don't give a sh1t anymore.

Turbo_Steve
11-06-2010, 09:03 PM
I give up.

bradc
11-06-2010, 09:17 PM
Sure whatever.

Show me a dyno with a pod where it performs better than the stock setup with no other mods (ie fuel control or ecu tuned around it)

I've listed an example on a dyno and you just want to talk about all of these theoretical reasons about how it may be possible to make something better. So go on then, do it yourself and show me the dyno results.

Wodjno
11-06-2010, 09:21 PM
We wouldn't have people like Wodj who sit there, look at CVR4 and go..."hmm...I think I might just go and try doing it my own way and see if it goes bang"



Contrary to popular belief ! I don't resemble the last 6 words in the above paragragph !!

Otherwise i would have killed more engines than the actual "Zero" that i haven't!!

AlanDITD
11-06-2010, 09:53 PM
Sure whatever.

Show me a dyno with a pod where it performs better than the stock setup with no other mods (ie fuel control or ecu tuned around it)

I've listed an example on a dyno and you just want to talk about all of these theoretical reasons about how it may be possible to make something better. So go on then, do it yourself and show me the dyno results.

Brad genuine question mate how many results have you seen that are bad on a dyno or 1/4 mile, not that just felt bad.

I know alot of people say things feel this or feel worse etc...when i put a 3" exhaust on my car with the RPW downpipes the car felt slower...but it knocked 2 tenths of the 1/4 mile time and that was consistently and with a *cough* pod filter...

So yeah not picking just wondering how many?

bradc
11-06-2010, 10:05 PM
There have been a few people on ozvr4 and Jeremy's one on here. I know it isn't a massive number but I still haven't seen a single dyno result with a pod and with stock where the pod makes more power.

AlanDITD
11-06-2010, 10:10 PM
There have been a few people on ozvr4 and Jeremy's one on here. I know it isn't a massive number but I still haven't seen a single dyno result with a pod and with stock where the pod makes more power.

Nah thats cool mate....but i know were looking at stock car with standard airbox, vs stock car with pod..

But isnt it more relevant to compare with a modded car? I.e when more air flow is required?

bradc
11-06-2010, 10:14 PM
yes and no. The problem with a pod is that it changes the shape of the air so that the small part of the maf that air is actually measured through is receiving a different amount of air compared to the rest of the maf. This shape isn't going to be changed in principle from 260 to 300hp at all, if anything if the shape is wrong then things will only get worse as horsepower is increased as the stock ecu does go to richer settings when it thinks more air is going through.

AlanDITD
11-06-2010, 10:19 PM
So were not really arguing wether pod filters are crap or not more how can the air be stablised before it hits the MAF without using the standard air box?

POD ON MAF = ****E i agree all day, but i think possibly where people have the pod maybe in the wing where the inlet pipe can fill with air well before hitting the MAF therefore being stable and dense may work...or a variant of that.

Anyway only real way to know as everyone agrees is on a rolling road.

Wodjno
11-06-2010, 10:22 PM
My argument is still Air Density :D

bradc
11-06-2010, 10:25 PM
If you had a long enough section of straight pipe after the pod the airflow could stabilise itself enough to be able to flow through the maf so that the maf is able to read it properly.

But at the end of the day you are only going to be about as good as the stock setup after a whole lot of tweaking. The other problem is that the VR-4 engine bay isn't big enough to have a long enough section of straight pipe!

VR4Kaos
11-06-2010, 10:52 PM
i think my car is a hell of a lot more responsive since putting the standard airbox on but can't get me engine managment light off since putting the stock box on wtf
but will bring the pod to RR day and test it out if ya'll want no probs

bradc
11-06-2010, 10:55 PM
Have you reset the ecu since putting it back on?

Good to hear the car is a lot better with the stock airbox on.

VR4Kaos
11-06-2010, 11:35 PM
Have you reset the ecu since putting it back on?

Good to hear the car is a lot better with the stock airbox on.
i have mate ive disconected the battery several times even over night but it still on :(/wall

Ryan
12-06-2010, 12:12 AM
Connection to the MAF secure? If the MAF is disconnected you'll see the Check Engine Light come on.

Kenneth
13-06-2010, 11:35 PM
Anyway only real way to know as everyone agrees is on a rolling road.

This is the point which really frustrates us over in NZ.
Those of us who have been part of the club for 5 or so years have seen a number of rolling road days with cars of various states of tune, with and without pod filters.

Every time a car with a pod filter runs on the dyno it performs poorly compared to cars which are of the same modifications. Usually even worse than less modified cars.

An example is a car with Pod filter, Intercooler, EBC and exhaust vs one with just an exhaust.
The car with the pod filter got ~163KW at the wheels, the other did 172KW at the wheels.

Another example was one which went up against my car. Not sure how many of you remember OSiRiS?
Lots of mods but had a pod filter. I had a few mods also but at the time I did not have a boost controller. I was returning to the Dyno to get a decent result as the previous time I only got 150KW at the wheels due electrical missfire (need new plugs)

Going for a drive in his car it felt very punchy compared to mine and I was a bit nervous because he had bet his would do better than mine.

Result was he got under 140KW at the wheels, I had just over 180. Thats a big difference. The dyno operator didn't even do the full 2 runs on the other car, he came out and said the AFR was just stuffed and there was no point in continuing as something was obviously wrong with the fueling.

These are 2 results from probably a good 4 years ago now. We have seen it time and time again.
It might be more obvious to us here because our cars which run well have a habit of pulling out good numbers on the dynos (which the UK members usually question).

Added to the side by side test by Jeremy and continued evidence to support our position, vs ABSOLUTELY NO evidence on the contrary, perhaps Brads' frustration over people continually questioning pod filters and then not wanting to believe they don't work on VR-4 MAFs, can be better understood.

Ryan
13-06-2010, 11:48 PM
/applaude

VR4Kaos
13-06-2010, 11:48 PM
i would of thought the main issue with em would be the heat the pull into the maf esp on higher modded cars as these get even hotter think the best mod i done so far to my car was getting rid of the pod and putting on the stock box

Kenneth
14-06-2010, 12:09 AM
It is more complicated than that, though temperature IS a factor.

Desired Air Fuel Ratio is calculated from a table which has AFR defined per LOAD and RPM

The MAF is used heavily to calculate Load. Temperature also affects Load. So if the MAF is reading incorrectly due to issues with the air, then the Load calculation is going to be out. If you then add on the temperature difference (if it exists) to that, the Load calculated then gets adjusted to compensate.

So now the Load is way out, so the ECU picks up AFR and Timing parameters based on a Load value which the engine is not seeing.

This is mainly an issue in open loop where the O2 sensor is not being used. It is also a bigger issue when you start flowing more and the change in AFR and Timing are larger due to reaching the outer mapped parameters.

Glad you got a standard airbox and have found it to work out :)



i would of thought the main issue with em would be the heat the pull into the maf esp on higher modded cars as these get even hotter think the best mod i done so far to my car was getting rid of the pod and putting on the stock box

CANDEE
14-06-2010, 12:34 AM
Ill bring my 2 c into this. :)

Firstly the comparison was done on Wynn(VR4 Mad)'s car. :)

And yes we do have the comparison sheets which I will get him to dig out for you all...

An interesting result is that the car lost 11kw while gaining 1psi of boost, so going off Andre's advise that 1psi of boost = 10kw, the car effectively lost 21kw......

The AFR's also went haywire, which I will get Wynn to post up as well. :)

We didnt have enough time to try the pod on the end of a stabilising pipe to see if the issue corrected itself.

J

bradc
14-06-2010, 07:54 AM
I love you two. Thankfully the NZ members have sense.

Anderz
14-06-2010, 08:38 AM
If you had a long enough section of straight pipe after the pod the airflow could stabilise itself enough to be able to flow through the maf so that the maf is able to read it properly.

But at the end of the day you are only going to be about as good as the stock setup after a whole lot of tweaking. The other problem is that the VR-4 engine bay isn't big enough to have a long enough section of straight pipe!

Agree with you
A straight pipe section of 10*pipe diameter is recommended before a vortex flowmeter. With a 3 inch pipe this would be 76cm:shocked:
There should also be a straight section after the meter, but as long as 10D is not required. The MAF adapter and the pipe itself should also be the same size and oval shape as the MAF, othervise it will disturb the airflow

Stock airbox is probably designed so that the MAF sees a laminar airflow. The mitsubishi MAF only measures flow through a small area in the center, so it will misread for sure if the flow trought it isn't laminar.

bradc
14-06-2010, 09:02 AM
Indeed. I knew it was a long length, but I didn't know it was that long! To be fair though the inside of the hole coming up to the MAF is not 3" but it is fairly big.

I have posted up lots of things over the last 4 or so years about pod filters, most of them seem to be largely ignored or forgotten about by the UK members. Witness this one:

http://www.clubvr4.com/forum/showpost.php?p=461943&postcount=18

There are also the examples listed above. Time and time again pod filters fail to make good power on the dyno and yet people still try them. As Kenneth said above, I got frustrated the other day when people didn't listen to me. For this I do not make any apologies at all.

It isn't as if you are fighting against me. I understand if you are trying to argue with just me. But you aren't, you are arguing with Kenneth, dyno results and the way that mitsubishi designed the MAF, to measure a stable fixed percentage of laminar airflow coming past a single measuring point. Do you seriously think you can do better?

mattnz
14-06-2010, 09:23 AM
I would have thought that when the car is moving the stock setup will outperform a pod even more, with the snorkel giving a slight ram air effect.

bradc
14-06-2010, 09:33 AM
That may help a very small amount but I doubt you'd notice it on a VR-4. On a 2.5 n/a you might notice it a little bit.

VR4 MAD
14-06-2010, 12:45 PM
As requested, here are the graphs for my car from the dyno run Jeremy and I did with our cars a couple of years ago.

Spec. of my VR4 at the time of the run was standard apart from a Ralliart panel filter and a Ralliart exhaust back-box.

We booked an hour of dyno time with the intention of getting baseline runs before undertaking a series mods so we can gauge what, if any improvements the mods make.

With this in mind, I intended to try two POD filter configurations to see what effect the POD made compared to the run with the factory airbox.

Sadly, in the end we ran out of time to do the final comparison with the POD moved some distance from the MAF which was very disappointing.......... :angry: /Hissy :furious3:

It would have been interesting to see if the additional distance to the MAF would have resulted in the airflow turbulence from the POD to settle and allow the MAF to read correctly.

Photo 1 is of the Blitz POD directly attached to the MAF as is usual.

Photo 2 is of the arrangement I was intending to try as a comparison if time had allowed. This was just a temporary setup for the dyno run only and was never intended to be anything other than a test setup. And before anyone says anything, the two openings, one on the POD and the other on the intake tube were to be bloked off for the test run.

Photos 3 and 4 are scans of the results.

I have an AFR graph as well but only for the standard run so haven't attached that as it doesn't help.

Hope this helps settle the speculation regarding what effect PODs have, though this doesn't preclude the possibility that some PODs and fitting arrangements might improve on the standard airbox arrangement but till dyno run graphs are posted up showing results proving that, these should end speculation on what actually happens when a POD is fitted directly to the MAF...................... /catfight

End of story................ :furious4:

/toycar

35340

35341

35342

35343


Ill bring my 2 c into this. :)

Firstly the comparison was done on Wynn(VR4 Mad)'s car. :)

And yes we do have the comparison sheets which I will get him to dig out for you all...

An interesting result is that the car lost 11kw while gaining 1psi of boost, so going off Andre's advise that 1psi of boost = 10kw, the car effectively lost 21kw......

The AFR's also went haywire, which I will get Wynn to post up as well. :)

We didnt have enough time to try the pod on the end of a stabilising pipe to see if the issue corrected itself.

J

elnevio
14-06-2010, 01:53 PM
Wow, the increased boost is really noticeable! :)

And is it just me, or is the power graph really peaky? Although it might be to do with the scaling used!

Anyway, that's by the by. Good to see the graph up on here. /yes



Having reread this thread, I am actually a little mystified by this whole 'argument' thing. All I can really see is pretty much 99% concurrence with the fact that in the VR-4 scenario, a panel filter beats a pod filter for performance, backed up by anecdotal evidence and some empirical evidence too.

It seems that some of the initial issues appear to have been that there has been plenty of reference to dyno evidence, but no-one seemed to be able to point the doubters in the right direction. Now they have!

Of course, I would venture that one result does not a dataset make, but most of the time, the 'bum dyno' has only backed up what most people have said about the difference, so has generally been taken as gospel.

What appears to have got folk annoyed here is on one side, the apparent lack of actual evidence, and on the other side, the apparent lack of belief of actual evidence existing. :rolleyes4 Almost everybody has been singing off the same hymnsheet, but some of us might have been holding it upsidedown! :upsidedow

Unfortunately, a few have probably got a bit too emotionally involved, a few tangents have been thrown in for good measure, and at times it has descended into frankly childish and even abusive behaviour.

So, to move this forward, I would suggest that the further dyno results alluded to (I believe on OzVR4?) be linked to, and with any luck, some additional results may come out of the rolling road day this coming weekend.

That should give time to everyone here to step back from this thread, think about what may or may not have been said, then move on with life.

Let's stick to the facts and the subject material. Anyone wishing to deviate from this path will surely only serve to reignite this wholly-unnecessary 'argument' with petty, often unfounded, remarks.


This is generally a nice place to be - please can we keep it that way? /grouphug

AlanDITD
14-06-2010, 04:10 PM
The pipe you used though is the wrong type there mate...i used a full 3" pipe on the filter therefore not directing anymore air to the centre of the MAF.

With the setup in the pics i would have no arguments that the power and afr's would suffer!

miller
14-06-2010, 05:17 PM
....

Gowf
14-06-2010, 06:10 PM
I think my original point was the lack of empirical evidence available for this for from my own personal experience with a stock car with nothing on it but a HKS pod filter, made 211BHP at the wheels at 7psi. Now, ive got the graphs somewhere if you like, the car was run at Surrey Rolling road, which is a 4wd dyno dynamics dyno. I personally believe the results.

Now looking at this logicaly, if the arguement holds true, i would have had more power than that to start with yes? (it was 273 at the fly btw) which would imply that i had a stock car with far more balls than any of the others ive seen with 60,000miles on them.

That was my arguement.

Now thankfully some graphs have been posted up, and im not going to start the whole uk vs nz debate on dyno results again as i dont feel there is much need. But as an indicator of the difference in the boost curve it is certainly interesting.

AlanDITD
14-06-2010, 06:11 PM
....

Common mike share :D

bradc
14-06-2010, 09:07 PM
There is a certain level of irony as Wynn's car got 211hp at the wheels with the stock airbox, although his car is an auto so it was a little bit better than yours at the engine, around 227hp if it was a manual.

With the pod his made 202hp, so corrected for the auto losses Wynn had 215hp at the wheels.




I think my original point was the lack of empirical evidence available for this for from my own personal experience with a stock car with nothing on it but a HKS pod filter, made 211BHP at the wheels at 7psi. Now, ive got the graphs somewhere if you like, the car was run at Surrey Rolling road, which is a 4wd dyno dynamics dyno. I personally believe the results.

Now looking at this logicaly, if the arguement holds true, i would have had more power than that to start with yes? (it was 273 at the fly btw) which would imply that i had a stock car with far more balls than any of the others ive seen with 60,000miles on them.

That was my arguement.

Now thankfully some graphs have been posted up, and im not going to start the whole uk vs nz debate on dyno results again as i dont feel there is much need. But as an indicator of the difference in the boost curve it is certainly interesting.

bradc
14-06-2010, 09:12 PM
Nev, in response to your post:

I simply get frustrated when time and time again I explain the problems and people just don't seem to listen. If you give it a month there will be another thread with someone asking about pods and we will have a similar debate again. I hope that now with the dyno results from Wynn there will be a much wider agreement that pods suck arse.

On the note of dyno results, you guys are all having a bit of a play this weekend, why don't a few of you try out pods? I'm sure at least one car turns up with a pod. I would really like to see the results if the pods was moved between a few cars as well, from stock to reasonably modified (with boost, exhaust and intercooler ideally) to see just what happens.

Gowf
14-06-2010, 11:59 PM
There is a certain level of irony as Wynn's car got 211hp at the wheels with the stock airbox, although his car is an auto so it was a little bit better than yours at the engine, around 227hp if it was a manual.

With the pod his made 202hp, so corrected for the auto losses Wynn had 215hp at the wheels.


Where the irony? Mine made stock power that was my point as it was a stock car, only a pod on it.

So if Wynn's made more power than mine, in stock form, then its making more than stock power by using the stock airbox? Bit confused by that

bradc
15-06-2010, 07:59 PM
But your car wasn't making stock power, it was down a bit.

Gowf
20-06-2010, 07:42 PM
But your car wasn't making stock power, it was down a bit.


Correct me if im wrong sir, but 280ps is 276BHP yes? If so my car WAS making 3bhp less than stock power, which after 65000 miles is more than adequate id say! Especially if tolerancing is considered.


There is a certain level of irony as Wynn's car got 211hp at the wheels with the stock airbox, although his car is an auto so it was a little bit better than yours at the engine, around 227hp if it was a manual.

With the pod his made 202hp, so corrected for the auto losses Wynn had 215hp at the wheels.

And also Brad, going on this, if you take Wynn's standard car with more power at the wheels than mine (if it was manual) at 227BHP, that would equate to a flywheel power (going on the dyno dynamics calulated manual trans losses on mine from 211-273) at 293Bhp, Which is most definately unheard of over here! Maybe this just goes to show the discrepencies in the angle of inlination of your dynos in NZ!

bradc
20-06-2010, 08:06 PM
But do we know for sure that they make 276bhp out of the factory? Unless facelifts were bumped up another 10hp or something.

Oblivion
21-06-2010, 10:56 AM
Just out of interest, has anyone tried the ARC induction box for comparison?

CANDEE
21-06-2010, 11:21 AM
Correct me if im wrong sir, but 280ps is 276BHP yes? If so my car WAS making 3bhp less than stock power, which after 65000 miles is more than adequate id say! Especially if tolerancing is considered.



And also Brad, going on this, if you take Wynn's standard car with more power at the wheels than mine (if it was manual) at 227BHP, that would equate to a flywheel power (going on the dyno dynamics calulated manual trans losses on mine from 211-273) at 293Bhp, Which is most definately unheard of over here! Maybe this just goes to show the discrepencies in the angle of inlination of your dynos in NZ!
Both Wynn and my cars are facelift autos. :) Mine with 60,000km, and Wynn's with about 90,000km.

Also are you questioning the ability of one of the most respected tuner's on this side of the world? Just look what Andre did with DS9(and this isnt the only car he has worked on with epic results).

Also Im going to open a can of worms in this and dont believe any of this whole "flywheel horsepower" guff.... Its all too much up to the speculation of which formula you use, which can show incorrect results.. Therefore the correct unit of measure should be at the wheels/hubs depending on what dyno is used.

J

mike74
21-06-2010, 11:29 AM
my galoon made 284bhp at fly with ONLY a k&n panel filter added which would kinda tie-in with the alleged 276bhp (from factory) figure...possibly

chris g
21-06-2010, 12:42 PM
I agree that simplest approach is 'at the wheels', forget formula and fudging...

I know we have used formula for calculating engine bhp but simplest approach is best...

Whenever we mention bhp from RR, use at the wheel figure, common language, no confusion...

Gowf
21-06-2010, 03:00 PM
I agree that simplest approach is 'at the wheels', forget formula and fudging...

I know we have used formula for calculating engine bhp but simplest approach is best...

Whenever we mention bhp from RR, use at the wheel figure, common language, no confusion...


Common language? Not at all, totaly depends on how the dyno retards and calculates it power there of.

I do agree with the statement on engine power calcs etc and the only true way is on an engine dyno (which there are 4 sat in the next room to me now). However, rather than using an arbitary value why not use the dyno's retard to calculate it as it then does take into consideration the drive train losses.

My point is quite simple. Japan were never meant to make cars over 280bhp. If they did mod the facelift to make more power, why bother? Its a galant not an evo or gto!
You can say what you like about whatever, but the realy interesting thing is when a NZ map is sent over here, installed on an ecu, on a car with the same mods and very low milage and makes 40bhp less..... now thats an interesting result that i dont think you can put down to calculatory error.

So all that being said, you can only compare results from the same dyno's, and i know which one i would trust.

Gowf
21-06-2010, 03:21 PM
Both Wynn and my cars are facelift autos. :) Mine with 60,000km, and Wynn's with about 90,000km.

Also are you questioning the ability of one of the most respected tuner's on this side of the world? Just look what Andre did with DS9(and this isnt the only car he has worked on with epic results).


J

I am not quite sure how i am questioning a tuners ability as we are talking about cars in what is essential a stock state. So now matter how good a tuner is, he's not going to get more out of your stock car just by willing it to do more.

Further more, I am not just some keyboard warrior as brad put earlier in this thread. I work with people who used to work for magnetti marrelli, who have mapped all of BTCC and some of the WTCC.

So i find the statement about questioning tuners utterly ridiculous

chris g
21-06-2010, 03:33 PM
Surely it is a common language...

From a given RR day/session people say 280 bhp or 150 bhp and because we are using same std it is clear that we are referring to 'at the wheels...'

A shared, agreed, approach/language to describe a specific matter...

If we agree how we will describe it then no misunderstanding...

Simples, surely...

Gowf
21-06-2010, 03:44 PM
Surely it is a common language...

From a given RR day/session people say 280 bhp or 150 bhp and because we are using same std it is clear that we are referring to 'at the wheels...'

A shared, agreed, approach/language to describe a specific matter...

If we agree how we will describe it then no misunderstanding...

Simples, surely...


Yes i do agree, but using different dynos destroys that theory. they have to be of the same type for that to hold

chris g
21-06-2010, 04:03 PM
Yes its about our conversations/posts about a specific day and dyno

We seem to have realised/agreed that different operator/day/dyno are not comparable and definitely not the latter...

But if we always post of 'at the wheels' figures then it is at least understood that there is no calculation or fudge involved, even if figures are not comparable...

bradc
21-06-2010, 08:24 PM
I wasn't really referring to you as a keyboard warrior Gareth, that was aimed at someone else.

Over here virtually all VR-4's get 150kw to 160kw at the wheels when stock and running at stock boost values at a variety of Dyno's around the country. The cars in Wellington did get a bit more than this but they were at the hubs, not the tyres.

swinks
21-06-2010, 10:03 PM
Brad, still figures in NZL are not matching figures over here. You saying you get 206 to 218 bhp ATW on stock car, where here such figures are reached only after several mods and upped boost over 0.8 bar.

What I'm saying, you can't refer to your figures describing UK cars and vice versa. Apparently NZ and UK run two diffrent dynos. :whistle:

1timeVR4
21-06-2010, 10:27 PM
I have no dyno results but i currently have a hks shroom filter slapped right on the side of my maff, fuel consumption is high as she's running rich, and runs rougher than it should, certainly no where near its full potential.

Ive just put a red top in the boot, and ordered the bits to make a new airbox in the old battery space tonight. Hopefully (work permitting) I'l get onto it next weekend.

chris g
21-06-2010, 10:39 PM
This issue seems to have got new life again...

Disregarding the interesting but odd variation in bhp in NZ compared to the UK, the noted difference on RR between std intake and mushroom-type intake does seem to be valid and other experiences do seem to back up the view that std car is best suited to std intake...

At least that's how I make sense of this, I'm just an owner and not a techie...

ianturbo
21-06-2010, 11:11 PM
/popcorn /popcorn /popcorn
ian

Subaru ETA
21-06-2010, 11:19 PM
at the last dyno day my car made about 185kw atw with exhaust, decat, boost and standard airbox with k&n panel filter.

another member had front mount, boost, exhaust, pipe work and a pod filter. he was about 20kw down... (sorry i can remember who it was)

Ryan
22-06-2010, 12:59 AM
at the last dyno day my car made about 185kw atw with exhaust, decat, boost and standard airbox with k&n panel filter.

another member had front mount, boost, exhaust, pipe work and a pod filter. he was about 20kw down... (sorry i can remember who it was)

Sounds like that might have been Adie.

bradc
22-06-2010, 01:54 AM
I think so, or was it oblivion?

Ryan
22-06-2010, 01:58 AM
I seem to remember the disappointment being etched on Adie's face quite well :D

Oblivion
22-06-2010, 02:07 PM
I think so, or was it oblivion?

I had 167kw but only 8psi boost.

bradc
22-06-2010, 08:08 PM
8psi boost isn't bad for that power figure.

Ryan
22-06-2010, 08:13 PM
Ja, I had 167kW at 12.7psi.

bradc
22-06-2010, 08:22 PM
He has a manual, you had the equivalent of 179.5kw