jasonius

iTrader: (1)

Did a snorkelectomy on my 05 WRX last week (GP elbow) and in the few days since my KL has spiked (only amber iirc) a couple of times during WOT acceleration (once in second and once on the change up 3rd-4th ~6k)..!

Having been completely silent for as long as I care to remember (odd green at 6k+) it seems to be more than a coincidence and therefore, IMO related to the removal of the resonator..?

Was thinking of refitting the resonator anyhow as there seems to be no effect (not even induction noise wise..!) and I'm a bit worried about the possibility of water getting into filter box (yes I know it has drain holes). Also, having monitored airbox temps, the intake seems to suffer from more heatsoak, maybe the resonator, being cooled from fog cover, had some sort of chilling capacity..?

Either way, thoughts about the KL activity/snorkelectomy would be welcome..

Cheers,
J

bob r

iTrader: (46)

I did my own version of snorkelectomy which was to remove the resonator assembly and cut it at the point where it went into the wing. I then refitted it to the airbox and ensured a decent seal at the inner wing.
Afaik this kept the same intake temps, but increased airflow and induction sound.

jasonius

iTrader: (1)

The question is, could the extra air be effecting the map (leaning out a certain points) or should it be within the ECU's capability..?

Andy.F

Anything that affects the airflow pattern as it is presented to the MAF sensor can cause a false signal. This in turn can cause lean or rich running.

If the car is otherwise completely standard then it is likely to cope ok with this mod in isolation. If you also have a decat then you may just be getting to the point where the boost control is struggling a bit to keep things steady.

The ECU on the MY01 onwards cars is very clever, sometimes too clever. It will look at the air fuel mixture during cruise and light acceleration and adjust the fuel accordingly. This is great for cruise and light throttle.
It then takes one step further, based on what adjustments it may make at low flows, it can apply an offset to the fuel supply throughout part or all of load range, ie the car may run too lean or too rich when on boost as a result of false information supplied by the maf at low load. This must be compensated for in the airflow meter scaling tables.

This frequently causes issues at rolling road days when a fan is directed at the intake, or worse, underbonnet cone filter.

Andy

jasonius

iTrader: (1)

Ahh, cheers Andy..

I was actually surprised when I removed the snorkel as I thought it was going to be one long 'U' pipe, going down into the lower wing and then back up. In actual fact it's essentially an elbow from ram scoop into air box only with an extra bit going down into the resonator. Therefore I can't really see any advantage from removing it as the air flow/pressure should be the same.

The oem design obviously helps should any water get into scoop as it will just fill the lower resonator section (eventually draining out through the holes in it) without effecting air intake.
I also think there is some benefit from the fact that the resonator is surrounded by cold air via the fog cover. This, I believe, provides a cold air 'buffer' when sitting stationary in traffic etc. and explain why intake temps rise much quicker without resonator in place when at standstill.

Adds weight to the claim about how good the oem intake is..!

Going to refit snorkel tomorrow for these very reasons.

As they say, if you don't try you won't know.. At least it hasn't cost anything, provided I can sell on the elbow to someone (however, after this I'm probably stuck with it, lol)..!

jasonius

iTrader: (1)

Right, refitted it today and actually I'm not so sure about the temp findings..!

Although, the airbox temp doesn't rise so quickly with the resonator (when sat in traffic), once it does it takes longer to drop down again, even though it probably hasn't risen so much..??!!

I've also had a flick of amber on the KL, so it would seem not related to snorkelectomy..

I'm tempted into putting the GP elbow back on again as temps were better controlled when it mattered (ie when giving it some) and dropped lower (ambient) within seconds of moving off. The only thing I'm still concerned about is water ingress, particularly in heavy rain at speed as water could be forced into airbox as it has nowhere else to go, especially if an oncoming car slashed a large amount of water onto my car..!

Also bear in mind I've removed to rubber seal on the leading edge of the bonnet the goes over ram scoop/pipe..

I'll give it a few days of evaluating before making a decision as I'm only prepared to do this once more.. but any comments would help..

J

MrRA

I've got the GP elbow fitted to my Spec C. Haven't got a KL but have seen no adverse effects of it being fitted yet. My drive is on a slight slope and I was concerned about water going up the scoop. Opened the bonnet after washing to find nothing had really gone past the rubber seal, although you did mention that you've removed your seal so I cannot comment there. Maybe you could drill a small hole into the GP elbow if you're really concerned with water.

Bob Rawle

Jase Andy means did I ensure that the maf scaling only gave you a positive long term fuel trim IF it got carried through (which it doesn't always btw). Its not really clever at all else it would drop the long term trim as soon as it comes on boost ... but thats Subaru for you.

Intake temp won't be affected as long as you blank the hole where the "part two" moulding fits i.e. the one from inner wing to bonnet lip, without the resonator its doing nothing so that can come out as well.

Don't mess about drilling holes in things that arn't necessary btw, the liklehood of you getting water up there is no greater without it since its behind the wheel arch. Head on water at the bonnet lip stands as good a chance without the seals imho. the more mass you have attached to the intake the longer it takes to heat soak but, as you see, the longer it takes to release the heat, so remove it and mask off the inner wing where the "part 2" fits and see how that goes, more air equals more power and its easy to add some fuel if its needed !!

cheers

bob

Andy.F

I didn't really as I didn't know you had mapped it Bob ! Hence my reference to it being ok if it was the only mod from standard. I was commenting on what may happen to an unmapped set up

Andy

jasonius

iTrader: (1)

Hello Bob,
What I did was use an intake elbow in place of the resonator ie:

http://i20.photobucket.com/albums/b2...obybits058.jpg

Hence my concern about the direct route from the ram scoop into airbox. My thoughts were the ram effect from the front of the bonnet would be more direct without the resonator as it's more direct, however it would also be more direct for water ingress. Hence 'MrRA' suggesting a few holes in the elbow. However, I still think that in very heavy rain at speed, water could be forced into airbox..

Having taken a good look at the ram scoop, there are a few holes already in it and it's above the rad with some very hot pipes from header tank, running right underneath it..! (I could insulate the underside of the scoop like I did with airbox: Airboxinsulation3.jpg - Image - Photobucket - Video and Image Hosting

Thanks again for the input..

DeanF

iTrader: (1)

Regarding water & Snorkels..??

How do Mini Scoops with Induction Kits fair for water ingress @ speed ??

Surely they must get a soaking especially how it has been raining over the past few weeks.
Any potential issues there ??
Thanks

Dean

MrRA

I really wouldn't worry about water being forced into ram scoop. I used to have a Gruppe M Ram Air induction kit fitted to my CTR. If anyone has ever seen one of these in the flesh then you would instantly assume water ingress would be a problem. It draws in air from where the windscreen and bonnet meet using a little scoop. It is a carbon fibre box with a cone filter inside and if anything was going to suffer from water problems then it would be this but I never once suffered any issues with it, even on a rain soaked motorway at 80mph+. Have never heard of any other people using it to have any problems either. It had a small hole in it for water drainage. My point being that when these kind of things are designed, even aftermarket, problems such as rain water would surely be taken into account.