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Best Intake System?

Street Show

By Street Show,
in Engines & Forced Induction

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2BNVS Veteran

2BNVS

Posted
Posted

id go apexi over hks but i personally use k&n...reason i dont like hks is when i had it before, the foam after a while and runnin decent power would be sucked into the turbo or afm when i had that attached...

so i prefer the non foam types

ben...

Mr. Keets Grand Master

Mr. Keets

Posted
Posted

I cant remember where I got this but here it is

copyright Scott. GTROC Members Secretary.

"

Working as an Air Induction Designer for 6 years for a few of the worlds automotive companies, (Ford, VW, Aston Martin, Jaguar, Saab, Opel etc.) has given me a good insight into what does

and doesn't make a good induction system. I recently removed my air box and after quite a lot of research I decided to go for an M's system. This is just two aluminium adapter funnels, the same as Blitz, with K&N's.

My logic behind this decision is as follows:

HKS type foam filters allow a lot of dirt to enter the engine, especially if they aren't changed

regularly. As they use an open cell foam the dirt particles rattle around in the foam structure,

as the air does, and eventually finds a way through.

Blitz Mesh filters boast the filter down to 20 microns. I have extensive engine wear data showing

that particles down to 3-8 microns actually wear big ends and the rings. Being only a thin filter

medium there is no where to trap the dirt and it only takes a little effort to such it through. It may

be good for flow, although I seriously doubt this, but you want this power and the engine to last.

K&N type oil treated cotton filters do offer better filtration by virtue of the oil sticking and

trapping the dirt particles. Our suppliers of air filters have done a lot of work on oil migration

to the air flow sensor and have found little proof of this. I know people will claim that theirs

was effected by the oil, but as long as the filter isn't soaked in oil, there is little evidence.

We only treat ours with only 10-20 grams of oil. So be warned when cleaning yours. The use of

oil on a filter can not only improve its efficiency but can also triple the amount of dust it can hold.

This is why we only use oil when the vehicle only has room for a small filter and/or works in a

dusty environment, (e.g. S/America, Africa etc.).

Apexi's cone filter has a combination of all the others virtues with NONE if the down sides.

It has the bell mouth and other air flow aids, and the filter medium they use is recognised in

our business as the best. It has good flow characteristics as well as exceptional filtration

capacity down to the real fine stuff. The only down side for myself as a designer is the fact

it 3 times the price of paper, and making 1 million air box's a year we tend to look at price first.

But for us as an after market item the expensive price of the filter isn't as important and there

is only pennies in it. In my opinion they are the BEST filter on the market.

So why did I chooses the M's system. Well not wanting to sound like a tart, but the M's system

looked a lot neater and factory fitted look when compared to the Apex'i, and the performance

isn't that far behind the either. So for me K&N offered adequate protection as well as aesthetics.

All/most aid induction kit should offer lower restriction as long as it is clean and in good order.

But there is the problem of under hood heat. As long as the is some baffling and cool air ducted

in this shouldn't be an issue. The worst condition is actually when stationary, but this isn't a

problem as no power demand is being made on the engine. As soon as you do move off then

cool air will purge the system quite quickly.

Well I hope this has help in some way clear up some of the misleading quotes and claims

these manufactures put out.

Just one last nugget of information: at 7500 rpm and standard boost the air filters

have to clean 232 litres of air a second and 325 litres at 1 bar, No mean task.

Also check out http://www.mkiv.com tech articles"

I bought the Apexi power intakes and they work well and are quality....sound great :D

Beer Baron Grand Master

Beer Baron

Posted
Posted

personally I think the K+N filters or the M's kit (uses K+N filters anyway) is the best set-up. however on my car I use the apexi kit because it looks nice and is not far behind. :/

Omurru Veteran

Omurru

Posted
Posted

I rememebr seeing a website somewhere that had tests that showed flow rates and how small a particle they filtered down to can't remember the address of it now although the apexi ones came out streets above the rest. I use an apexi one in my commodore and have never had a problem with it. Will be changing over to apexi ones in the skyline as soon as I can get my adapters modified to fit. IMO there by far the best.

Busky2k Veteran

Busky2k

Posted
Posted

Never been a fan of metal or foam based filters. You want the filter to do its job, ie filter the air. And its so true that dirt in your engine accelerates wear. Its even easy to tell if you got a leaking air filter through an _oil_ analysis!

I believe its well worth trading a couple of rwkw for a filter that filters better.

Baysidebluebnr34 Rising Star

Baysidebluebnr34

Posted
Posted

I have a k&n pannel filter on my 34gtr I am haapy with that at the moment. The standard air box has two entrys for the air, the top one with the funnel and there is also a side entry. This side entry can get air from the inside the fender, from the factory they have a block on the side entry, all you have to do is pop is out and you have more cold air!!! cost= a bit of your time.

After doing this will will notice the induction has increased slightly and you can hear the standard bovs clearly.

N1GTR Grand Master

N1GTR

Posted
Posted
Go the factory airbox...

running std 32GTR airbox with a nismo filter element...

no complaints!

I tried that, and ive done the M's pods which are currently serving as paperweights, ive settled for an ARC airbox, it makes a little bit of noise, but the boys in blue dont seem to mind it (well, most of them)

GTRgeoff Grand Master

GTRgeoff

Posted
Posted

Apexi clean

apex_res.jpg

K&N clean

http://www.mkiv.com/techarticles/filters_t...k&n_res.jpg ssorry it won't let me link this one.

Check the packaging on K&N and it will likely have "For race use only" or similar.

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