Subaru EJ20 Induction Noise

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mshaw1980
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Subaru EJ20 Induction Noise

Post by mshaw1980 »

Hi all

When my subaru engined van is under load at about 3500 to 4000 rpm the induction noise is horrible. Its like the metal in the rear vents reasonates inside the van. I have a standard subaru airbox so could someone guide me in what parts they used to connect the airbox to an induction hose rather than the airbox being fed from the void behind the passenger side rear lamp.

Cheers
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)

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Aidan
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Re: Subaru EJ20 Induction Noise

Post by Aidan »

if you have the air box on the left side partly sticking into the space behind the lights then you want the diesel snorkel and suitable flexible pipe to connect to the airbox
251 129 533 B and 251 129 535 plus a round to oval adaptor and suitable hose, I actually had most of the parts in my hand last week, but I can't find the box they are in now so haven't got the part number for the oval to round adaptor but if the round hose is big enough and flexible it will fit the oval and then you may just need to adapt size to air boz but the Subaru has fairly large diameter intake like 70mm

mshaw1980
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Re: Subaru EJ20 Induction Noise

Post by mshaw1980 »

Thanks Aidan. Doesnt the intake snorkel cause a massive restriction in airflow which negatively affects power? I know that airflow would most likely speed up due to venturi effect but my van is not the fastest by any means so dont want to further reduce power?
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)

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Aidan
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Re: Subaru EJ20 Induction Noise

Post by Aidan »

if the snorkel is ok with a 3.2 six cylinder Oettinger I think it'll be fine with a 2 litre scooby
VW went to a lot of trouble quietening the air intake, the diesels in particular have sound deadening on tube below the snorkel and the hose to the air filter and the inside of the body
as you know the scooby sucks hard, which is why the original car intake is so convoluted in order to reduce intake noise

mshaw1980
Posts: 538
Joined: 10 Aug 2015, 06:50
80-90 Mem No: 14800
Location: Peel, Isle of Man

Re: Subaru EJ20 Induction Noise

Post by mshaw1980 »

Great. Thanks for the advice :-)
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)

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