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Performance air filter options?

5K views 15 replies 4 participants last post by  mapalfa 
#1 ·
I'm getting confused by all the possible air filter options.

My Brera is running everything pretty much standard at the moment, though as soon as my Fixitsan dongle arrives I'll fit the straight pipe I've got waiting and fully blank the EGR. What I thought was a possible oil leak near the turbo turned out to be weeping from the air intake, so that's been fully sealed with silicone tape. I've also got a Rutland Motors oil catch can waiting on a couple of fittings.

As I didn't know the recent history of the car when I bought it (full dealer history to roughly 80k then nothing till I bought it at 120k, though the air filter has a date stamp on it of 2014 so it must have had some work done) I spoke to Opie Oils who suggested running a cheaper/lower grade oil through it for a couple of tanks and then changing again once the EGR/DPF was sorted. I did that and also cleaned the throttle body and as much of the inlet manifold as possible, plus reconnected the swirl flaps using a repair kit as there was very little movement.

Once the EGR/DPF is done I'm looking to get a basic performance remap done, so I'm investigating the various air filter options. The problem is that there are so many my head is starting to swim. I don't want to do anything that can't be reversed leaving everything standard, but am quite happy removing bits and pieces that may not be optimal now.

I'm not looking for power gains from the filter, though a little bit extra is always welcome, but an improvement in the spool-up speed would be good. Some extra induction noise would be nice, but I don't want it to sound like a chav'd Corsa!

So, do I:
Remove the whole system (from the MAF) with an induction kit.
Leave the airbox in place (to provide waterproof airflow) and place an aftermarket filter just above the airbox.
Leave everything as it is, but replace the filter only with an upgraded one placed in the standard airbox.

Depending on the above, do I:
Route a cold air feed direct to the filter.
Route a more direct feed to the airbox.
Leave the standard air feed.

Also, what make filter do people recommend? The Pipercross filters give a good variety of options if I mount it outside the airbox (more length/offset variety), but most of the manufacturers have a straight drop in option if I go for the standard airbox option. I don't want to spend crazy money, but I'm not going to go cheap Chinese either (unless that's recommended by enough people, though I doubt that will be the case).

Finally, do I remove and blank the resonator box?

Thanks in advance:thumbup:
 
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#2 ·
Hey Map,

I recently have gone through the same thought processes with my V6 Brera. I wanted to get more induction noise so i could hear the car roar and i can safely say that i achieved it based on all the comments i received at the recent Pasta Run cruise (joint ferrari/lambo/alfa/fiat club annual event). Although i would have liked it louder still, i think the design of the Brera is what it is and i'm not going to be able to make it scream like a 360 with a tubi!

Anyway - I went for an Apexi Power Filter that i installed in place of the standard air box. It is a dry type filter - made in Japan - top quality and simply cleans with compressed air (no need to wash and re-oil like a K+N, and no problem with MAF's). I had the same set up on my 1998 GTV. I ran that set up for years with absolutely no ill effects - only masses of induction noise and smiles every day. So i replicated it on the Brera. The Brera induction noise is mostly noticeable in the higher rev range (whereas i found the GTV noisier through the whole rev range) and i think this is due to the position of the filter, semi enclosed behind the bumper.

I've run it for 3 - 4 months now. No problem with water ingress. I have removed the standard filter box and mounted it high where that would have been, in the 'hidden' part in front of the wheel well / behind the bumper effectively.

The 'snorkel' part that goes to in front of the radiator stays, so it's easy to retrofit the standard fitting.

The filter needs a generic adapter to mate to a standard (72mm???) opening that is your plastic OEM tube where you removed the OEM filter box. PLus i made a little bracket to give the filter a bit of extra support to hold it - i didn't want the whole weight of the filter to be held by the intake tubing and it rattling about.

NOW (FWIW).... to further improve the sound i also removed the rear muffler boxes on the Brera and am running straight pipes. And teh combination of the two sounds awesome. I'll have to get a youtube vid at some stage and post it. Together they are loud enough to make the better half whinge and complain that it's "too noisy" and quiet enough to not attract the cops attention (if you are careful on the throttle through the booze bus :).

Trav
 

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#10 ·
I went for an Apexi Power Filter that i installed in place of the standard air box. It is a dry type filter - made in Japan - top quality and simply cleans with compressed air (no need to wash and re-oil like a K+N, and no problem with MAF's). I had the same set up on my 1998 GTV. I ran that set up for years with absolutely no ill effects - only masses of induction noise and smiles every day. So i replicated it on the Brera. The Brera induction noise is mostly noticeable in the higher rev range (whereas i found the GTV noisier through the whole rev range) and i think this is due to the position of the filter, semi enclosed behind the bumper.

I've run it for 3 - 4 months now. No problem with water ingress. I have removed the standard filter box and mounted it high where that would have been, in the 'hidden' part in front of the wheel well / behind the bumper effectively.

The 'snorkel' part that goes to in front of the radiator stays, so it's easy to retrofit the standard fitting.

The filter needs a generic adapter to mate to a standard (72mm???) opening that is your plastic OEM tube where you removed the OEM filter box. PLus i made a little bracket to give the filter a bit of extra support to hold it - i didn't want the whole weight of the filter to be held by the intake tubing and it rattling about.

Trav
Cheers again for the input. Based on your description and photos I had a play around using some bits from a cheap and nasty induction kit I bought for the tubing. I had to use a bend as the filter is a bit too wide and was fouling the inside of the bumper, but other than that I've gone for a very similar setup to see how it goes. If all is OK I'll replace the filter with a decent quality one.

Again as a temporary measure I've made some shielding with heat resistant foam insulation (the type you can lay electric underfloor heating elements direct onto) and cable tied it into place. the front I cut to shape once the bumper was back on and simply tucked it up over the lip. If this works I'll replace it with something more solid, but this will do for now.

First impressions are good. The turbo seems to spool up a tiny bit quicker (though that's possibly wishful thinking) and the induction noise is more obvious but still subtle.
 

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#3 ·
Oh yes, and of course, you need to put all those covers back - the under engine cover and teh wheel well cover. Those stop the muck getting in. I am in Australia so we dont drive on muddy salty roads and i'm not doing water crossings. I've read all teh other threads with the for's/against's and the flames etc about this set up asking for trouble.

All i can say is i haven't had any trouble, and i like it.
 
#4 ·
Looks like an interesting option. I've not seen those before.

I'd have to find some way of mounting it that allows for the under-tray to stay off without risking water ingress. The front sub-frame rots like hell if left in contact with water sitting in the under-tray, so I keep mine off.

Cheers for the info:biglaugh:
 
#5 ·
I'd love to hear your car OziGTV! And by straight pipes do you mean resonators or no rear mufflers at all?

Going in deep water is bad for so many other hot parts on the car so it's best to avoid deep water anyway, but if anyone wanted more protection from water on a V6, maybe you could mount the filter just infront of the maf, and whip up a custom airbox/heat shield from fibreglass to prevent the filter sucking in hot engine bay air, so air comes in from the oem air intake hole in the body.
 
#6 ·
...and by 'straight' pipes i mean 'curved' pipes with a couple of twin 70mm chrome tips. hahah. So yeah, no rear resonators at all, just pipework. Flat out at work today so i didnt' get a chance to video it and pop it online - i've asked a fellow Alfisti at work to help me do it tomorrow.

I spent ages trawling youtube and the net looking for options for sports mufflers. They all sounded rather similar (youtube limitations granted) and rather pricey.

By the end of it i decided stuff it, i'm not spending $1,000-$2,000 for a couple of back boxes and went to a custom exhaust place to get them to pop on some small resonators. Before he went to the effort of selecting and welding up resonators, he ripped off the boxes and started it to hear the "raw sound" and it was good.

So I went straight pipe. Best $150 i ever spent.

I am actually considering removing the centre muffler and going a small hotdog or straight through glass pack to make it even more aggressive - but i think that will p-ss off the neighbors and wake the kids when i get home at night. So i'm carefully considering that option.
 
#12 ·
#7 ·
oh yeah, and mapalfa, regarding the undertray, given the mounting position of this filter, you could make a small flat tray to shield the filter and mount it inside the compartment. That would allow you to leave the undertray off i suspect. A bit of fluffing around of course.
 
#8 ·
I'm looking forward to hearing this thing, don't forget to record some induction noises!

You could have the best of both worlds, and install a center resonator, by also installing an exhaust valve before it splits into two pipes. There are electric ones on ebay that start at around $100, but i don't know how good they are, best to get one where the motor and gearbox aren't in contact with the exhaust, so the butterfly valve is actuated via a steel link. You don't want it to close fully, just enough to put the car in quiet mode to keep the mrs and neighbours happy, and a push of the button makes it a straight through system.
 
#11 ·
I didn't mean an exhaust cut out Ozigtv, i meant an inline one like this:
http://www.ebay.com.au/itm/3-0-Elec...031356?hash=item1c5854b7bc:g:EhYAAOSwDNdV3Ai8
I don't like how the motor and gearbox are almost directly connected to the exhaust heat, i much prefer ones where the motor and gearbox can attach to the car chassis, and there is a steel cable linking the gearbox output to the valve.

So if you installed this on your current setup just before it spilts into dual outputs, you could trigger between between your current sound and a quieter restricted exhaust. It wouldn't be able to get it as quiet as a good chambered oem style muffler can, but maybe half as loud as the current setup. You might have to trim the size of the butterfly valve if there is no adjustment for restricted mode, so you can reduce flow by around half, which would kill top end power but improove low end torque. There are oem cars that use these to improve economy, power and control noise.
 
#13 · (Edited)
#14 ·
OK Guys - here's the link to the sound of the Brera:
https://youtu.be/wvxAa2GEcYA

Map - looking good. I see that you have mounted it with the silver curved pipe. That does make it low. I attached mine straight to the black OEM tube.

Alfafanboy - yeah i have often thought about setting up a car with a system like that. Unfortunately the Brera has bugger all space with the 4wd system etc - i dont think there would be much space to mount both a loud and quiet system. Maybe when i get my Maserati! HAHHAHA.

Also, i hear that valved system get rattly when old.

Anyway, let us know what yo think of the video - in this edit he's put lots of revving in it - not exactly showing the reality of normal everyday driving...
 
#16 ·
OK Guys - here's the link to the sound of the Brera:
https://youtu.be/wvxAa2GEcYA

Map - looking good. I see that you have mounted it with the silver curved pipe. That does make it low. I attached mine straight to the black OEM tube.
Sounds great - growls rather than screaming like some rice-rockets.



I had to fit the curved pipe as that filter was too wide and fouled the inside of the bumper stopping it going back on correctly. If I decide to stick with a setup along these lines I'll be getting a decent quality filter and will make sure it's narrower so I van lose the pipe.

I'm still toying with the idea of getting a replacement intake tube and cutting it shorter in the engine bay so I can mount the MAF further up and leave space for the filter just above the standard airbox position.

The problem is that intake tubes cost way too much money from specialist breakers and I'm working on a limited budget at the moment. My planned brakes rebuild/upgrade is going to take 500-600 quid, depending on if I need caliper rebuild kits, so this really is a bargain basement project for now.

I watched a video on youtube where someone built a composite intake by moulding with the wrap they use for broken limbs. He then wrapped it in carbon fibre for extra strength and neatness. That also looks like an interesting option, perhaps using cheap ali flexi pipe to get the basic shape first and then wrapping that, but again it's not a project for now.

BTW, my wife drove the Brera yesterday and told me that there was a scraping noise when she changed gear at higher revs - I had to explain about the noise from the new filter:teacher:
 
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