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Induction Noise
landfall - August 13th, 2015 at 06:20 PM

Having just fitted a pair of Weber 34 ICT's to my bug, the induction noise is quite loud. No complaints about jetting or performance, just the induction noise.

Now I am thinking it may have something to do with the firing order of the engine?

Can somebody give me their opinion about fitting dual throat 40mm Webers instead? Would they be as noisy or less?


OZ Towdster - August 13th, 2015 at 06:55 PM

Webers will be worse if you don't already like the ICT's .
The solution is to fit some QUALITY sound insulation to the engine side of the firewall panel , and i don't mean some crap you buy at your local auto shop , it will need to be approx 25mm thick foam with a vynal barrier also in it for best results which will give noise absorbsion and a barrier to help stop it moving through your firewall .
And how do i know this otherwise useless information , yep i worked in acoustic engineering for some 10 odd years a while back


psimitar - August 13th, 2015 at 07:13 PM

And make some jute pillows for the inner roof channels that lead sll the way up from the engine bay. You'd be surprised how much noise can travel up them into the headlining :)


Camo - August 13th, 2015 at 07:44 PM

Quote:
Originally posted by psimitar
And make some jute pillows for the inner roof channels that lead sll the way up from the engine bay. You'd be surprised how much noise can travel up them into the headlining :)


My thoughts are that the sound travelling up the 'C' pillars is the main culprit, having experienced this in my Beetle. I had twin 45 webers and you couldn't really talk to the passenger. With that said, I had removed all the expanding foam that someone had put in there and now have nothing.

Went to efi, turbo and that quitened it down ;):yes::lol::lol::lol:


Bizarre - August 13th, 2015 at 09:13 PM

Making up a centre mounted air cleaner like the CSP setup reduces noise dramatically


psimitar - August 13th, 2015 at 10:21 PM

A good quality tarboard in the engine bay that includes the side engine trays will also help the enclose the soundwaves within the engine bay. It's all well and good fitting deadener and absorber to the inside of the firewall, and should also be done, but reducing the soundwaves that actually hit the firewall is a big difference.


landfall - August 14th, 2015 at 07:26 AM

Thanks for the replies.

It seems that I will have to live with it, or rather the wife will have to get used to it, I rather like it.

OZ, I have gutted the car and applied Dynamat everywhere followed by a quality sound insulation covering (definitely not cheap junk), on the fire wall it is on both sides and also on the sides of the engine bay. Plus the underside of the guards and floor pan have been sprayed with sound deadener.

I have thought about the centre mounted air filter system, but have also read somewhere that the foam socks over the air filters may help.

Had 45mm DCOE Weber on our mini and it appeared to be about the same noise level.


waltermitty - August 14th, 2015 at 08:00 AM

change your cam


grumble - August 14th, 2015 at 08:54 AM

Just practice saying eh, what? answering different snippets of conversation and things like you see happening in nursing homes so that you are ready for the inevitable hearing reduction that comes with this.:crazy: :tu::tu: Bizzarre is right the centre mount filter definitely helps.


1303Steve - August 14th, 2015 at 01:09 PM

Hi

I have to agree, fit a centre air box and run tubes into it from each carb, a late Beetle plastic airbox would be idea.

The nice sound would still be there just subdued a little

Stevel


1303Steve - August 14th, 2015 at 01:15 PM

like thsi http://www.csp-shop.com/cgi-bin/cshop2/front/shop_main.cgi?func=det&wkid=...


landfall - August 14th, 2015 at 01:40 PM

Quote:
Originally posted by 1303Steve
like thsi http://www.csp-shop.com/cgi-bin/cshop2/front/shop_main.cgi?func=det&wkid=...


728Euro, I think I'll live with it.

I did also fit a multi media system with 3800watt amp, so I'll just listen to more music.


1303Steve - August 14th, 2015 at 06:56 PM

Dont buy one of them, it wouldnt be hard to make


landfall - August 14th, 2015 at 07:25 PM

Steve, I'll give it some thought for sure. Thanks

I've looked at the Bernie Bergman site with interest for possible ideas.


1303Steve - August 14th, 2015 at 08:04 PM

This is what the late Beetle air cleaner looks like, a few bits of silicone hose and you connect into the base of it

http://vwparts.aircooled.net/v/vspfiles/photos/113-129-607L-2.jpg


1303Steve - August 14th, 2015 at 08:14 PM

some good reading http://www.clubvw.org.au/oldart017#fue02 


landfall - August 14th, 2015 at 09:16 PM

Quote:
Originally posted by 1303Steve
some good reading http://www.clubvw.org.au/oldart017#fue02 


Thanks, now I have something to work from.

Much appreciated and will be interesting to see if I can gain any success.


1303Steve - September 29th, 2015 at 08:28 AM

Just saw this


1303Steve - September 29th, 2015 at 08:29 AM

Thats a stock late model Beetle air cleaner