Hi guys,

 

I just down to my local Autobacs (in Japan) to buy an Apex'i Power Intake Filter. The guy I spoke to looked it up in the catalogue and said that it was strongly recommended that it be installed with the Apex'i Air/Fuel computer S-AFC-II. I had a look at the catalogue myself and he was indeed right.

 

I asked him about it but he didn't know much so I got him to call Apex'i and ask. They said that without the fuel computer you risk having rough idle and running slightly too lean risking engine damage. Something to do with the "dual funnel" design of this filter resulting in too smooth airflow for the air meter to measure accurately. Not sure though, my Japanese was failing me at this point. But I did understand that it would only be very slightly lean, not enough to cause noticable detonation, but enough to potentially cause engine damage over a longer period of time.

 

He then tried to sell me a HKS filter which apparently comes with no such recommendation / warning. I really want the Apex'i though since it's best for both flow rate and quality of filtration.

 

I know that many people have this Apex'i filter installed and I believe they do so without having the fuel computer in. Also, I kind of find it hard to believe that if this is really a problem then it will only affect the Apex'i filters.

 

I really don't want to cause any engine damage just for the sake of a few extra horsepower and I don't really want to have to pay for an Fuel / Air computer just yet since my car isn't yet modified anywhere near enough to really justify it (all I have is a cat-back exhaust).

 

Does anyone have any knowledge of this? What do the people say who are using this filter? Anyone caused any damage this way? I'm really looking for people who have fitted A/F meters and can comment on the effect this mod really has becauseI don't think it would necessarily be noticable without accurate guages.

 

I'll be back in the UK in about a month now but would like to have this fitted here before leaving because it only costs 30 quid here. Of course, that's not including the S-AFC-II !!!

 

As always, thanks for your help. :bow:

Sorry Rory, I have a Blitz so not up on the Apexi. I'm just intrigued with the 300zx scene in Japan, I mean, is it goodies galore there? Have you seen many tricked up Z's? Being right hand drive - one contact we really could do with is a decent floor mat manufacturer! Any chance?

(sorry for off topic bud)

Rory

 

I have this filter now, but can't monitor fuel / air ratio. I've never heard anything like this however, apart from some people mentioning the mesh in the AFM creating a bit of turbulance needed for a better reading.

 

Interested to find out though, although my chip increases fueling anyway so should be a problem.

sorry bud i cnt help u with ur question

can u email me at yp11@le.ac.uk i wanna ask u a huuuuge favour

 

cheers

I thought the funnel of this filter was designed to cause the needed turbulence?

sorry bud i cnt help u with ur question

can u email me at yp11@le.ac.uk i wanna ask u a huuuuge favour

 

cheers

 

Same here bud :D

 

Cheers

Mathew

redstarinc@hotmail.com

The best person to answer this is prob smithy as he's the fella who supplied me with an apexi intake and my car has been running perfect for over a year now....i cant help but think its jus a marketing sheme to sell more of their products.

I have A'PEXi filter and have had no such problems. Also the A'PEXi is the best filter for filtering and air flow and the worse was HKS, according to a test which was done on in a mag a few years ago.

 

The cone part on the A'PEXi is to cause turbulance.

Most after market filters create a column of air down the intake, so there is more air flowing down the sides of the hose than in the middle, almost creating a vacume in the middle.

 

The MAS is positioned in the middle of the intake hose, and so the reading shows a low amount of air because of reasons said above, most of it is rushing past it along the side where the MAS can not detect. This causes the ECU to set up the fueling incorrectly because there is many time at much air going into the engine than it is detecting in the middle of the hose.

 

The comon result of this is engine stalling when putting in the clutch at high speeds or when letting off the accelerator at high speeds.

 

A'PEXi put the cone into their filters to make the air jumble up as its going into the airfilter. This forces the air to go down the intake hose and past the MAS more evenly so the MAS can get a more true reading of the amount or air and thus the ECU can properly correct the mapping for the amount of air entering the engine.

The best person to answer this is prob smithy as he's the fella who supplied me with an apexi intake and my car has been running perfect for over a year now....i cant help but think its jus a marketing sheme to sell more of their products.

 

 

Its not a gimik.

 

Go onto TT.net and look at the tech about stalling and K&N filters. The fix it you stick a ball of masking tape to the top of the filter so it creates turbulance.

 

It is not a gimik.

 

Has any one seen that video of the person who said adjust the screw which is stopping the butterflys in the plenum opening up fully? Right at the end of the vid he has an incar view of him driving when he floors is. Watch what happens when he lets off, all the ignition lights come of for a few seconds becuased it stalled, most probably because of this reason.

Fitting an AFR wouldn't fix it anyway!

You might be able to correct the problem with it but unless you set it up on a rolling road and can get the true air figures it's no use.

Sounds like they are trying to find excuses to book it in for a tuning session to me!

The twin cone design of the Apexi is to minimise turbulence not induce it, that's according to Apexi'i anyway. I guess this is the reason why the other filters manage OK without the mixture adjustment.

 

Have a look here:

 

http://www.apexi-usa.com/intake_powerintake.asp

Not sure that this is particularly limited to the Apex'i but anyway....

 

I'll look into the floor mats - is it OEM ones you're after or just good quality, designed for Zed ones?

Actually, marketing scam was my first thought too, but considering that there's plenty of competition for filters in Japan I would imagine that one would be more damaging than helpful to sales.

 

I trust Apex'i too in anycase. Their stuff is quality.

Well yes, that goes without saying really. Just buying and installing the AFC wouldn't be enough - it would need rolling road time for proper set-up. But, given that this is done properly it would compensate for any mis-reading by the air-flow meter, which I believe is the fundamental problem here.

Also, sorry, a bit more. It's not the shop trying to persuade me to buy this AFC, it's Apex'i themselves. I was going to fit it myself, the shop knew this too. To be honest, I don't think the shop could care less about my engine, they only really sell parts, they don't have a rolling road, so there's nothing really in it for them.

 

If anyone wants to see the Apex'i recommendation for themself I've found it here:

http://www.apexi.co.jp/products/suction/katarogu_data01/01_p_intake_na_tur1030.html

 

Look under Nissan and look for the correct engine code. To the far right is the recommendation for using the AFC. It's in Japanese but I think you'll get the idea.

I'll look into the floor mats - is it OEM ones you're after or just good quality, designed for Zed ones?

 

NOT OEM ones, I hate those and threw mine straight in the bin! Oops, prob could've sold them. Quality mats designed for the Z would be good.

Any info/contacts would be excellent!

Its not a gimik.

 

Go onto TT.net and look at the tech about stalling and K&N filters. The fix it you stick a ball of masking tape to the top of the filter so it creates turbulance.

 

It is not a gimik.

 

Has any one seen that video of the person who said adjust the screw which is stopping the butterflys in the plenum opening up fully? Right at the end of the vid he has an incar view of him driving when he floors is. Watch what happens when he lets off, all the ignition lights come of for a few seconds becuased it stalled, most probably because of this reason.

 

 

are u a parrot stu?

Complete rubbish - Apexi are just trying to make more money out of you. The ECU is more than capable of compensating for the (very slight) increase in air flow.

 

Get the Apexi filter though. Its an excellent product.

I know that the computer is more than able to componsate, but it can only do this if it is getting an accurate reading from the MAS. The suggested problem is that due to the low turbulence generated by the dual funnel design of this filter the MAS consistantly unreads the correct value, at least at certain engine speeds resulting in the fuel mixture being just slightly too lean.

 

Apparently, this is undetectable without the use of accurate air / fuel meters but is also significant enough to potentially cause engine damage longer term.

 

I'm not really looking for people to tell me that they've fitted this filter to their car and it works fine - I know if I fit this filter to my car it will appear fine. What I'm looking for is people who have done before and after fuel mixture comparisons to see how significant the running lean actually is.

 

I don't believe it's a marketing scam because it' not a general recommendation by Apex'i, it only applies to certain model Nissans where the MAS is locating very close to the filter. It applies to Skylines, Zeds, and 180SXs and a few others. I genuinely beleive that there may be an issue here. Apex'i should know - they designed the filter, and if they are "strongly recommending this use of ..." then I expect it is more to protect themselves from litigation from customers than to make a quick buck selling more parts.

 

At the moment I'm running on 100 octane Japanese petrol. When I come back I'll have ot use 98 at best. The last thing I need is the engine also running slightly too lean due to an air filter.

.

 

I don't believe it's a marketing scam because it' not a general recommendation by Apex'i, it only applies to certain model Nissans where the MAS is locating very close to the filter. It applies to Skylines, Zeds, and 180SXs and a few others. I genuinely beleive that there may be an issue here. Apex'i should know - they designed the filter, and if they are "strongly recommending this use of ..." then I expect it is more to protect themselves from litigation from customers than to make a quick buck selling more parts.

 

 

Erm is'nt the fitting of the filter right onto the MAF an Apexi trade mark, I:E with the exception of one or two models, 99% of Apexi dual funnels fit onto the MAF on any make of car. So if that was the reason behind it, it would apply across the board.

smithy

So whats the conclusion after all of this?

 

Is it or isint it not safe to use apexi filter as i want 1!

 

Fas

Hi. Thanks for your input.

 

Yes, you're right. I'd only looked at the filter for the Z, looking at the other cars' fitments I'd agree with you. However, it doesn't detract from the fact that there is something specific about these Nissans which, according to Apex'i requires the use of the AFC.

 

Maybe something to do with the design of the MAF, or possible just that during testing Apex'i found these cars to have problems with mixture.

 

It'd be interesting to know what exactly, but I doubt we ever will!

 

It's also interesting that on the US Apex'i website there is no such recommendation. It's exclusive to the Japanese site.

 

I'm cetainly not trying to give these products a bad name, the reason I'm started this tread is that I'm not prepared to accept any of the other brands (that don't require AFCs). Apex'i make the best filters and I want one, but, I also love my car more than I love the power. If you know what I mean.

 

Cheers!

I've also found the recommendation in English here:

 

http://www.takakaira.com/

I'm going to post the same question onto http://www.twinturbo.net I'll put the thread into the technical forum with a similar title so anyone interested can follow the story. I guess there are more people out there with access to Air / Fuel meters.

I also just realised I'm spelling A'pexi wrong - me stupid. :o

Is this still going on?

 

Loads of people on here have put A'PEXi filters on and not had anything remapped. You should reset your ECU so it can learn again