Air box to reduce noise on my 4108?

[ianj99]

Been following this with interest, in fact I posted earlier.
My BMC thumper has no air filter or air box at all so I am thinking now of a bit of a diy jobby just for the sake of curiosity. Am I right in thinking an air box off any motor, with a suitable adaption made from air intake pipe will do the job?...obviously it will have to fit in the space available and be able to secure somehow, but I have noticed the air intake is actually threaded, but I have not been able to find the size or thread yet. Plenty of scrappy's about to have a mooch around so it should be fun trying

This is where I got the Ford Ranger one I used. They often have other types and it is clearly easier if the outlet is the same dia as your engine inlet.
Bigger = better. I suspended mine under the cockpit using shock cord about a metre from the engine.

http://www.skan4x4.com/ebay-shop/

 

[nigelmercier]

This is where I got the Ford Ranger one I used. ...

Thanks for that, just bought one http://r.ebay.com/o6WvqR

What did you do about the hole where the air sensor goes?

 

[ianj99]

Thanks for that, just bought one http://r.ebay.com/o6WvqR

What did you do about the hole where the air sensor goes?

Sealed up. Though I did consider being a nerd and fitting a sensor and making a digital display !
Ian

 

[nigelmercier]

... I used a 76 to 60 silicon hose reducer from another ebay seller. .... [with] more hose and a 45deg elbow so its about 700mm from the engine. ...

Do you have eBay item numbers or links for these?

 

[ianj99]

Do you have eBay item numbers or links for these?

The stainless reducer was from this company, costing a few quid. Just give them the outside diameters you need. I also used one to join the injection elbow to the existing exhaust hose.

http://www.ebay.co.uk/itm/All-Size-...er-Flared-Connector-Flange-Tube-/321476839655

The silicon hose was from here:

http://stores.ebay.co.uk/autosiliconehosesoutlet/

 

[nigelmercier]

Thanks Ian.

Did you use a filter? Mine came with one, pretty clean especially after I hosed it out. I don't think I'll fit it, but I did wonder about making some foam baffles.

 

[ianj99]

Thanks Ian.

Did you use a filter? Mine came with one, pretty clean especially after I hosed it out. I don't think I'll fit it, but I did wonder about making some foam baffles.

Yes the Ranger box had a brand new filter in it so I left it in - its massively oversized for the boat engine so removing it should not have any effect on the airflow and will assist in noise reduction. I would have tried removing it, but the dungeon under the cockpit is cramped (3' -4' headroom and a tight squeeze to get in) and my arthritic neck doesn't like being contorted so somewhere I try to avoid entering.

However it was a paper one so I will keep any eye on it in case it gets damp. It should be okay but I will probably remove it for the winter in case of condensation.

 

[gandy]

I was just wondering what the disadvantages would be to simply making an air box out of light plywood, maybe lined with some sound deadening pads.