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hi there guys,

so i have a 2.0 sport impreza so its na. my latest mod was a hks mushroom induction kit. the nas have an air box which comes off the throttle body. i pulled that airbox off and directly attached the hks mushroom as a reverse fitting so that cold air is fed directly from the bonnet scoop. the air box had three hoses which i disconnected and covered with etape for temp. i feel like the cars hesitating to put power down compared to the standard airbox. is this due to the hoses? what can i do with those hoses? kayzarh said they wer pcv hoses but i havent a clue what to do with them and if thats the reason im losing power? can someone help? i will post pics tomorow morning when we get some daylight

cheers!


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  • savage bulldogs
    savage bulldogs

    Tbh I don't know much about the na boxer set up but generally na engines rely on back pressure.   So big bore zorsts and induction kits can make you loose torque and power .   As i haven't got

  • Scoobyghost
    Scoobyghost

    Could that filter facing backwards be causing some air supply issues?

  • Greenmamba
    Greenmamba

    Blocking off pcv hoses isn't helping as the crankcase needs to breathe and with what you've done, I think this restriction could be affecting power delivery.

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  • Author

so thats the setup very basic and simple, but the those three hoses as can be seen from the pics which are covered with etape i dont knw if thats whats slowing my power down. has anyone else had this problem?

Tbh I don't know much about the na boxer set up but generally na engines rely on back pressure.

 

So big bore zorsts and induction kits can make you loose torque and power .

 

As i haven't got a scooby do what those pipes are for ,I'd Probably start by bunging the leccy taped pipes with a suitable sized bolt and jubilee clip .

 

Hopefully this will either cure the lack of power or rule the pipes out as the issue .


Blocking off pcv hoses isn't helping as the crankcase needs to breathe and with what you've done, I think this restriction could be affecting power delivery.

  • Author

Thanks for the response savs, ghost and greenmamba.

so i pulled off the tape and the hoses seemed like they wer sucking in air. kayzarh said that u need it to be open and in a clean area as u do not want it to suck in water and debris.

as for the power delivery its better but still a bit hesitant.

i was thinking of maybe getting the front area of the old airbox and maybe using it to shroud the mushroom and also feed the hoses back into it.

will do that tomorow morning, hopefully we see some results!

but i think savs is right u do tend to lose power with zorsts and inductions i reckon.

and scoobyghost eventually ill probably reposition it with some piping to where the turbo induction kit goes and get a cold air feed pipe into there but i wanted to be sure that its worth fabricating a pipe for, lets hope it works out! 

thanks all for ur responses!😊👍🏻

Cold air = power.

If you ask me, you ain't getting a drop of fresh air from that position, but what you are getting is warm air from one of the hottest parts of the engine bay.

 

Warm air is just as bad as lobbing in 87 Ron fuel.

 

Don't worry we sort it when im back 😂

 

Sent from my MX4 Pro using Tapatalk

 

 

Didn't know the pipes were crank case breathers as I've only seen a boxer na bay once (in the flesh)

 

So yep don't completely block them off as the need to breathe, but don't let them suck in debris or moisture either .

 

If your still gonna run the induction kit and can't fit the breather /pcv system back to oe , get a vta catch can plumbed in asap


  • Author

im going to give that airbox idea a try today see what happens. itll mean the pipes go back in place but still having the mushroom on. and iv realised the engine bay feels like its hotter than usual when i go for a drive! i definitely need to do something about it! kayzarh come bak soon missing you bro!😂😂 and cheers once again everyone will keep u updated!

Rice rice baby rice rice

 

Sent from my MX4 Pro using Tapatalk

 

 

  • Author

lol its not like iv got sti stickers all over it! still says sport matey!😉👍🏻 and i dont have forged pistons but i tell u what i do have...

  • Author

FORGED SPANNERS 10mm😂😂😂

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removing airbox will be causing air turbulence issues over the maf, mix that with heat soak and pcv's 'there's your problem'

basically this a detuning mod, even forced induction subarus can have power/smoothness issues with filters similar to these unless fitted well and air flow mapping adjusted.

Subaru airflow sensors are very precise and easy get issues when change mechanical air intake without changing digital data .


I had this exact same problem on my 2003 wrx stuck a cheap short ram on, messed up the power and would not rev out, so tried airbox back on with inch sized holes bored in it, same thing, put standard air box on, back to normal, turbulence over maf is real and bad, and heated air is awful, don't know if this relates to your model at all but thought I would put it out there, i now have a quality cold air feed induction kit fitted on a different scoop, all good

  • Author

thanks mr b and piggysniffer.

so basically i should stick to the stock airbox right?

i thought i was mafless though so thought would all be well. but i think ur right. i reach eff it quite easily and so im probably eventually going to put the stock airbox back on ahahhaha.

cheers guys, was worth a try but i think your right, will stick to the standard airbox. sometimes stock is best😂😂😂 not always but sometimes😂

Do sports start with power then.

 

 

U really do learn something new everyday

  • Author

lol ahahhah yep they come from the factory with sh#tloads of power but as u mod it gets slower and slower😂😂😂

I suppose its a good job sporters fit bonnet vents to cool all that loss and add much needed drag 😂

 

Sent from my SM-G930F using Tapatalk

 

 

  • Author

the best mod for us sporters is go faster led lights, i cant recommend them enough! fitting them on will take u to stage 4 750bhp. you can ask litchfield, andy forest or bob rawle. theyll all tell u the same thing!😂😂😂

Wonder if i could chop the lil sti for one lol

 

Im only jokin ive had 4 sports in my younger days and id swap my sti in a heartbeat for my first one wen i was 18 lol

 

T722 MOF in green full turbo rep except the bonnet ironically lol

 

 

Edited by Rps

  • Author

i knw lol no harm in a bitta banter here and there! 😂😂👍🏻

and theyre so fun right! ahahhaah all the good looks a little less aggresive but can still do the odd car here and there ahahahha😂👍🏻 This subarus actually my first car. I had to wait one and a half years after i bought it to finally get it insured!

I had remote neons on one of mine and a flamer kit lol talk about bieng the sh it lol keep ur veyrons my underpowered 2l spits flames haha i could break into it in about 15 seconds too as i used to live on the top of a hill surrounded by fields and if the car was running it would lock its self if the door blew shut and i was always doing something tjat required the the engine running but me not in the car.

 

10 years later im thinking why didnt i just leave the window open 😐

 

Sent from my SM-G930F using Tapatalk

 

 

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