Cone filters? (Again!!)

[Jesus-Ninja]

OK, I know this has been done to death, but I've been a little bit out of the loop recently.

Have we now confirmed that a cone filter (eg Apexi) is fine on a stock MAF, provided there is a decent enough run of straight tube before the MAF? My intention is to run the cone into a 90 degree bend, after which there will be a 300mm straight bore of 3" before the MAF.

Ta!

[Davezj]

from what i remeber of the threads on here that is the way it should be done if using a cone filter. if you actually need to use a cone filter.

[Jesus-Ninja]

I need / want to clear some space in the engine bay, and doing this seems to be the most effective way, given that I'm rebuilding the front end.

[Nick Mann]

It's all about the flow. You need minimal turbulence. I would guess the filter design will play a part, as if it creates a vortex or mental turbulence then it's unlikely a short bent pipe will straighten it all out. One other idea was to pack straws or similar in the pipe to sort out the flow.

[swinks]

It's been already done, no problems whatsoever Nick. :)

[John TheAntique]

Buy Steve's Vipec then you wont have to bother.

[Jesus-Ninja]

It's been already done, no problems whatsoever Nick. :)

Nice. Parts ordered. Full rebuild of the boost pipe work from the Y piece through to the plenum. Am also replacing the weird wobbly cold pipe that runs to the front turbo.

[Jesus-Ninja]

It's been already done, no problems whatsoever Nick. :)
swinks - out of interest, and before I fab something up, is there something off the shelf that will interface between the MAF and a length of 3" pipe?

[c0xxy]

most of the pod filter adaptors would do that, with a bit of silicone hose

[Jesus-Ninja]

most of the pod filter adaptors would do that, with a bit of silicone hose

Cheers :) But which? Something for an evo? Like this? http://www.ebay.co.uk/itm/Air-Filter-Inlet-Adaptor-Mitsubishi-Evo-7-8-9-/290467549852?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43a137129c

EDIT: Just seen it has dimensions. That will do perfectly :D

[c0xxy]

i would say so, i bought an adaptor with a 5 inch outlet for an evo and had it on my galant, the last legnum came with a 3 inch and they swapped fine. although, both mine were a metal plate with a circular band welded to it rather than a pretty moulded thing like that!

[swinks]

swinks - out of interest, and before I fab something up, is there something off the shelf that will interface between the MAF and a length of 3" pipe?
I think Ash explain a lot.
Mine is: Apexi filter (battery location), then adapter to 102mm hose, 90 degree silicone bend (102mm hose), MAF adapter to 4in (102mm) and MAF itself in pretty much the same place where is stock one.

[Kenneth]

Cheers :) But which? Something for an evo? Like this? http://www.ebay.co.uk/itm/Air-Filter-Inlet-Adaptor-Mitsubishi-Evo-7-8-9-/290467549852?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43a137129c

EDIT: Just seen it has dimensions. That will do perfectly :D
Do not get that adaptor, I guarantee you will have problems with your MAF using it.

You need one like this: http://www.trademe.co.nz/motors/car-parts-accessories/mitsubishi/engines/auction-536273252.htm

[Jesus-Ninja]

Do not get that adaptor, I guarantee you will have problems with your MAF using it.

You need one like this: http://www.trademe.co.nz/motors/car-parts-accessories/mitsubishi/engines/auction-536273252.htm

Cheers Kenneth.

Presumably because you need an inlet that is at least as wide as the MAF?

I was planning on running 3" (76mm) from the filter to the MAF, hence the selection of adapter. Didn't see any great benefit of going 4.5" all the way from the filter to the MAF, as the rest of the system is only 3".

You reckon running 3" from the filter (about a 400mm run including the elbow at the filter) and then upping to 4.5" before the MAF adapter (like the one you linked to)?

Alternatively, I could run 114mm all the way up to the MAF, but then I have plenty of 76mm pipe (silicone and ally) and would rather just shell out for a reducer than a whole load of 114mm kit.

[wintertidenz]

It's 4 inch piping - the airflow doesn't get altered as much with the 4" adaptor.

[Jesus-Ninja]

It's 4 inch piping - the airflow doesn't get altered as much with the 4" adaptor.

What's 4 inch? The back of the MAF is a 3" bore, and the adapter Ken posted is 114mm, which is 4.5 inches.

Sent from my GT-I9100 using Tapatalk 2

[wintertidenz]

The adaptor I have is a 4" one and from the back of the VR4 MAFs I've seen it is 4" to the divider pipe. It makes sense to keep it all the same.

[Jesus-Ninja]

Weird. My MAF, is definitely 3"

58908

I agree with the principle of keeping it the same but, that said and thinking about it, going bigger is preferable to going too small as the MAF, as standard, "sees" a gaping great airbox.

[swinks]

Nick, I'd recommend front MAF adapter minimum 4 inches openning (102mm).
Also, MAF to rubber divider hose is approx. 85mm, not 3in. At least mine was :)

[Jesus-Ninja]

Nick, I'd recommend front MAF adapter minimum 4 inches openning (102mm).
Also, MAF to rubber divider hose is approx. 85mm, not 3in. At least mine was :)

Cheers, Tomasz.

Weird about the MAF measurements. As you can see, the ruler doesn't lie! :) I put the verniers on it, and it's definitely 76mm internal diameter. It's about 81mm external diameter, and the rubber divider hose is correspondingly about 82mm internal diameter. The rubber hose does get a bit wider further down the throat though.

So, ally 114mm MAF adapter ordered (the 76mm plastic MAF adapter will go back in a box of other bits I need to return to the same place)

I will run from the 85mm Apexi cone outlet to a funnelled 102mm apexi adapter then 102mm from the filter adapter before stepping up to the 114mm to the MAF adapter.

[Kenneth]

Hi Nick

The problem is not the internal diameter, it is the entry.
It works on the same principle as having trumpets on your throttle bodies. The curve (and you don't need much) on the inlet allow the air to enter the "pipe" in a more even fashion, improving the flow around the edges of the pipe resulting in more overall flow.

The main problem with our MAF is that it is only measuring the airflow through the centre portion. The ECU does some calculations based on the air through the centre and assumes the rest. If you change the way the air enters the MAF and add turbulent air or screw with the air flow on the edges, the ECU has no idea. The wider the adaptor, the more even the air flow is going to be through the edges of the MAF.
You could tune it out but I always fear that the response wont be linear and one day the conditions will be such that it will read closer to "normal" for a bit and destroy the engine.

The #1 issue with pod intakes (and ESPECIALLY with the form of adaptor you originally linked to) is that it causes the MAF counts to increase by quite a bit, screwing fuelling and ignition because it believes it is running an much higher load.

Carsten (Gly) had this very issue on his. I flashed his ECU to "fudge" the timing and fuel (was running on 12.5 AFR values rather than standard 10-11) and it was still over fuelling. He changed the adaptor (from the one you linked to the one I linked) and all of a sudden he had detonation problems because he was getting more accurate MAF counts. I re-set his AFR / timing values back to factory values and viola, all fixed.
I know of lots of other times, but the one above is the one where I can say for 100% certain it was the Pod adaptor and nothing else to do with the intake setup which was causing the majority of the problem.



Cheers, Tomasz.

Weird about the MAF measurements. As you can see, the ruler doesn't lie! :) I put the verniers on it, and it's definitely 76mm internal diameter. It's about 81mm external diameter, and the rubber divider hose is correspondingly about 82mm internal diameter. The rubber hose does get a bit wider further down the throat though.

So, ally 114mm MAF adapter ordered (the 76mm plastic MAF adapter will go back in a box of other bits I need to return to the same place)

I will run from the 85mm Apexi cone outlet to a funnelled 102mm apexi adapter then 102mm from the filter adapter before stepping up to the 114mm to the MAF adapter.

[Jesus-Ninja]

Hi Nick

The problem is...

Cheers, Kenneth :) "Correct" parts ordered. Interestingly though, the stock airbox does nothing to funnel the air in nicely, though. It just has the MAF located in the side of a flat panel.

Has anyone ever tried running an airbox with no panel filter, but a cone on the inlet to the air box? Weird I know, but just curious :)

Sent from my GT-I9100 using Tapatalk 2

[Kenneth]

The stock airbox doesn't need to do any funnelling since the MAF does this itself. The job of the airbox is to provide an enclosed area post filter where the MAF has enough room to feed evenly.

You could run a pod on the end of the airbox and remove the the panel and it should work OK. There is no point though, since the panel has been shown not to provide any significant restriction. By removing the funnel and adding a pod, you lose any cold air benefit without any significant flow benefit. The flat panel may also help to remove turbulence from the air, though I haven't seen that proven.

It is possible that the funnel does impede induction, however I haven't seen that proven and there are many of us with very good power figures who use the OEM airbox setup. It could be more cost effective to cut into the airbox before the panel and add another duct into a cold air position low in the wheel well. An added benefit of keeping the upper funnel is that you wont hydraulic your engine easily.

Of course if you make significant intake changes (new turbos, complete custom pipe work etc) it might be a good time to come up with a different solution. Short of that, my opinion is that there are better things to do for greater benefit.

[Jesus-Ninja]

Pipework all in

58985

Might have to replace the 45deg silicone hose with an ally one.

[John TheAntique]

Not wishing to be disrespectfull but all that work does what exactly?

[Jesus-Ninja]

Primarily replaces the pipe work that got destroyed in my smash, and given my plans it seemed pointless to put the same back in. It also removes the crappy wobbly pipe to the front turbo, hooks into a big FMIC, allows me to run an Apexi filter, moves the dump valve to where it doesn't get smashed about and covered in crap, and is ready for turbo upgrade.

Also there's coolant pipework in there. Evo 789 rad meant different pipes. And finally there's some oil cooler and filter relocation lines.

Sent from my GT-I9100 using Tapatalk 2

[CANDEE]

Not wishing to be disrespectfull but all that work does what exactly?
By the look of it there is:

Pod where the battery used to be, then a 90 deg pipe going to a 4" pipe to the maf(this should in itself straighten the airflow from the pod), then the maf goes into the factory maf - turbo pipes.

Then it looks like Nick has redone the cold side of the intercooler to the throttle body, in silicon and alloy, moving the bov up closer to the throttle body.

The thing that looks weird to me is how the pipework to the front turbo has been done.... Jesus-Ninja Nick do you have any pics of this without the i/cooler to throttlebody pipe in place?

[Jesus-Ninja]

No pics CANDEE, but I'll try to sort some later. Basically, from the stock T, it goes through a 57mm to 54mm 45deg elbow which follows the top of the gearbox. Then it couples into a 54mm to 45mm 90deg elbow to turn into the turbo. I've buggered about with stuff in there so much over time, that I can't remember why the stock pipe would be so weirdly shaped, as I have nothing in the way.

Sent from my GT-I9100 using Tapatalk 2

[John TheAntique]

I can see what's been done and if it is for an upgrade of turbos I can see the point but as it stands how much diference does it make? Does it alter the torque curve by more than 1% for example?

[Jesus-Ninja]

I can see what's been done and if it is for an upgrade of turbos I can see the point but as it stands how much diference does it make? Does it alter the torque curve by more than 1% for example?

I doubt if it will make any perceivable difference to the performance, in and of itself. .

Sent from my GT-I9100 using Tapatalk 2

[scott.mohekey]

One thing it does do VERY well, is look amazing.

[CANDEE]

I've buggered about with stuff in there so much over time, that I can't remember why the stock pipe would be so weirdly shaped, as I have nothing in the way.
Its because the factory pipe is the same on the auto and manuals, and with the auto there is an external filter right next to the factory pipe..

[Jesus-Ninja]

Its because the factory pipe is the same on the auto and manuals, and with the auto there is an external filter right next to the factory pipe..

Ahhh! :) I thought I'd removed something at some point :D

[Jesus-Ninja]

The thing that looks weird to me is how the pipework to the front turbo has been done.... Jesus-Ninja Nick do you have any pics of this without the i/cooler to throttlebody pipe in place?

As requested :) You can just see where it picks op the stock pipe work with an ally coupling which includes a T for the DV to return to. This is basically the same as the wobbly pipe, although marginally closer to the rear turbo.

Ideally, the DV would vent to just behind the MAF, but the MAF goes straight into the stock Y piece that feeds the two turbos. A job for a future upgrade I think.

59004

59003