Airbox trunking

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carlp
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Airbox trunking

Post by carlp »

Can somebody please tell me how long the piece of airbox trunking should be and how the inlet end is fixed? I bought replacement airbox recently and the length of trunking is quite short (less than 1 metre) and seems filled with a layer of foam held in by a wire sprint reducing the airflow? The trunking seems to be the same paper covered foil trunking as used by the Elan? My current trunking is held in place by a cable tie?

Thanks
Carl
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Johnwindwood
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Re: Airbox trunking

Post by Johnwindwood »

The foam lined trunk is the original type which is no longer available-replacements are just alloy tubing.
The inlet end should be held by a metal bracket which fits across to the radiator- it has two metal semicircular clips. The tube pushes into this and is then held by a rubber strap (Although I use a cable tie.)
Kind regards

John

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Hawaiis0
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Re: Airbox trunking

Post by Hawaiis0 »

The spring wire retainers usually snap off leaving one half which is not much use or if both go you will just see the original weld mark.
Umm! What to do next?

Johnwindwood
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Re: Airbox trunking

Post by Johnwindwood »

Hawaiis0 wrote:The spring wire retainers usually snap off leaving one half which is not much use or if both go you will just see the original weld mark.
Which is exactly what ours was like-got a replacement from Lotusbits.
Kind regards

John

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carlp
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Re: Airbox trunking

Post by carlp »

If anybody had some closeup photographs of the bracket I would appreciate it?
Thanks
Carl

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72 Elan Sprint
97 Alpina B10

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DavidOliver
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Re: Airbox trunking

Post by DavidOliver »

Merlin Motorsports provide ducting and a wide variety of elongated intakes to fit in reduced spaces.

Dave the cog.

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Re: Airbox trunking

Post by soldave »

Anyone have any ideas what the foam was meant for? Only thing I can think is some sort of sound deadening, but I'm not sure how effective it would be at that.

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Re: Airbox trunking

Post by richardw »

soldave wrote:Anyone have any ideas what the foam was meant for? Only thing I can think is some sort of sound deadening, but I'm not sure how effective it would be at that.
I believe it was to dampen resonance in the inlet tract, which can lead to a surprising amount of noise. The airbox itself is covered with sound deadening material.

You can get 90mm flexible silicon trunking which is a good fireproof alternative to the original; it should be possible to line it with foam (5mm thick was used originally I believe) and maybe use the original trunking wire to hold it in place?

It is also important to use the intake piece that is attached to the mouth of the trunking to smooth airflow.

ATB Richard
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carlp
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Re: Airbox trunking

Post by carlp »

Any idea how long the piece of trunking was?

Carl
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richardw
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Re: Airbox trunking

Post by richardw »

carlp wrote:Any idea how long the piece of trunking was?

Carl
From measuring mine, 1m should do it.
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carlp
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Re: Airbox trunking

Post by carlp »

richardw wrote:
carlp wrote:Any idea how long the piece of trunking was?

Carl
From measuring mine, 1m should do it.
Thanks..
Carl

87 Excel SE
72 Elan Sprint
97 Alpina B10

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Hawaiis0
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Re: Airbox trunking

Post by Hawaiis0 »

richardw wrote:
carlp wrote:Any idea how long the piece of trunking was?

Carl
From measuring mine, 1m should do it.
Different to mine as it's about 39.4 inches :roll:
Umm! What to do next?

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Re: Airbox trunking

Post by igg-hiss »

Hawaiis0 wrote:
richardw wrote:
carlp wrote:Any idea how long the piece of trunking was?

Carl
From measuring mine, 1m should do it.
Different to mine as it's about 39.4 inches :roll:
What going on mine is 0.0497 Chain?
The Lotus Eclat, a lot like the English Whisky company: comes from Norfolk and better than you are often told it is.

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FroggyEclat
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Re: Airbox trunking

Post by FroggyEclat »

Hello all,

A first contribution. Just measured mine and 850 mm should do it.

have anybody tried, 90mm diameter, l=300mm can be stretched to 1000mm ?

https://ja.aliexpress.com/item/Free-Shi ... 90255.html

Neil

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Re: Airbox trunking

Post by Pete Boole »

igg-hiss wrote:
What going on mine is 0.0497 Chain?
:lol: :lol: :lol:

Pete

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