912 air filter help

For you flat four Porsche 912 fanatics

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MartinP
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912 air filter help

Post by MartinP »

Some of you will know that I have just replaced my exhaust, flapper boxes etc. I thought that perhaps taking the straight-through exhaust out might reduce the noise levels in the car, but no. My opinion now is that it is the fault of the K&N filters and think that I need to change to the standard filters. From other people's experience, are the original air boxes significantly quieter than a pair of K&Ns, and do they have a noticeable effect on the performance?
Thanks :)
ex-Porsche 912 owner, currently making do with a 1971 Volkswagen Beetle
1964 Series IIA Land-Rover
http://www.thatchamclassic.co.uk
Evil J Guano
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Post by Evil J Guano »

Not sure changing filters will make that much difference, do you have the bulkhead sound pad fitted? It's usually pretty grotty 15mm thick pad at back of engine bay. You might want to consider lining back shelf and passenger compartment with something like Dynamat for real sound deadening. There are a lot of frequencies in an engine 'note', carb suck will only be a part of the overall (rather nice) din :)

http://www.dynamat.com/products_automot ... ction.html
Gavin Joule
912uk
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Post by 912uk »

K&N's will produce more power but like only a few horses. I think it's more noise making it sound like more power rather than it is..

Standard are good all rounders I have to say I still run standard. Also as for sound proofing.. I have very thick sound proofing both inside the engine bay and out side the engine bay and it still is not quite.. reduced hmmm sort of.. but not really..
MartinP
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Post by MartinP »

While the engine was out, I put some sound and heat-proofing in the engine bay. Problem was, as it is metal-backed, it just made the K&Ns sound even worse: like two machine guns going for it! I've just pulled it out which has made it almost bearable again, but I need to find a more civilised long-term solution. I don't mind a bit of noise and racey feel for the odd drive, but for three hours each day it gets a bit unbearable!
ex-Porsche 912 owner, currently making do with a 1971 Volkswagen Beetle
1964 Series IIA Land-Rover
http://www.thatchamclassic.co.uk
912uk
Nurse, I think I need some assistance
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Post by 912uk »

Check out woolies they do all the bits you need on Gavins web site.
Ian Gunney
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Post by Ian Gunney »

Martin

I have a pair of the large cannister type filters you are more than welcome to try (your car is still running Solexes)

Ian
1966 912 Karmann Coupe - polo red.
1972 914/6 GT replica - 2.7 - signal orange.
1961 Standard 217 Tractor.
2003 Boxster S.
1967 Alfa Giulia Sprint GT Veloce.

http://www.redcastleclassics.com
MartinP
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Post by MartinP »

That's very kind of you Ian. I am coming to Cardiff at the weekend - are you around then at all? Would be great to try some before spending the money and then deciding that perhaps they weren't what was needed!
ex-Porsche 912 owner, currently making do with a 1971 Volkswagen Beetle
1964 Series IIA Land-Rover
http://www.thatchamclassic.co.uk
Ian Gunney
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Post by Ian Gunney »

Hi Martin

yes should be around on the weekend

my contact no is 07711 433630 - I'm 2 mins from junction 30 of the M4

will pm you some directions

Ian
1966 912 Karmann Coupe - polo red.
1972 914/6 GT replica - 2.7 - signal orange.
1961 Standard 217 Tractor.
2003 Boxster S.
1967 Alfa Giulia Sprint GT Veloce.

http://www.redcastleclassics.com
MartinP
DDK forever
Posts: 515
Joined: Mon May 07, 2007 8:23 pm
Location: Berkshire

where does this bit attach to?

Post by MartinP »

Thanks to Ian's generosity, I have just fitted a pair of standard air filter boxes to my 912 to try out for a few days. Just one question though - the 'T' piece that sits on top of the fan housing has another inlet at the bottom of the T. Is this supposed to join onto something in addition to the side exit pipes connecting to the air boxes?

Apologies, because I'm sure it's a simple matter that I am overlooking...

Many thanks!
ex-Porsche 912 owner, currently making do with a 1971 Volkswagen Beetle
1964 Series IIA Land-Rover
http://www.thatchamclassic.co.uk
Ian Gunney
DDK 1st, 2nd and 3rd for me!
Posts: 2326
Joined: Thu Nov 13, 2003 7:42 am
Location: Cardiff

Post by Ian Gunney »

Martin

can't think off the top of my head - will check on my car later if you like

Ian
1966 912 Karmann Coupe - polo red.
1972 914/6 GT replica - 2.7 - signal orange.
1961 Standard 217 Tractor.
2003 Boxster S.
1967 Alfa Giulia Sprint GT Veloce.

http://www.redcastleclassics.com
912uk
Nurse, I think I need some assistance
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Joined: Wed Nov 12, 2003 11:02 pm

Post by 912uk »

I just received some Ketch solex air filters in the post today no Santa has not arrived early. I just couldn't help my self when i saw then in the US.. so I will clean these up and see what they are like.. I was told they do rob power in the mid range.
hunter
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Post by hunter »

Hi Martin

The rear exit on the t-piece is supposed to also have a pipe connected to it.

This then runs across the back of the engine to the right hand side of your engine bay and connects to the right hand side longitudinal (sp?)

This is supposed to help direct some warm air to your carbs on cold days when your heating is turned on.

Hope that helps
Darran

Bahama Yellow 67 912 - sold
Ian Gunney
DDK 1st, 2nd and 3rd for me!
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Post by Ian Gunney »

Darran beat me to it!

hope the filters have the desired result

by the way Darran, posted off the two exhaust parts yesterday....
1966 912 Karmann Coupe - polo red.
1972 914/6 GT replica - 2.7 - signal orange.
1961 Standard 217 Tractor.
2003 Boxster S.
1967 Alfa Giulia Sprint GT Veloce.

http://www.redcastleclassics.com
hunter
Married to the DDK
Posts: 235
Joined: Sat Oct 01, 2005 4:09 pm
Location: West Yorks

Post by hunter »

Cheers Ian

Got them yesterday.

Will have a look at them this weekend and get back to you.
Darran

Bahama Yellow 67 912 - sold
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