Advice on Air filters

[pauljones]

Hi all.

Im currently looking for an air filter setup for the twink. Idealy after the biggest that will fit within the confines of the bay with minimal work.
I will also be installing trumpets within it as i dont have any on my relatively thin k&Ns

What are people using at the moment?

Looking forward to summer driving.

Regards all.

Paul

[Foxie]

Hi all.

Im currently looking for an air filter setup for the twink. Idealy after the biggest that will fit within the confines of the bay with minimal work.
I will also be installing trumpets within it as i dont have any on my relatively thin k&Ns

What are people using at the moment?

Paul

I prefer to take cool air from the nose before it is heated passing through the rad, so I have a large cone filter on the front of the standard 3.5" duct to the standard airbox.

[pauljones]

Thanks Foxie,

I dont think thats an option on mine. I have a full size rad fitted and theres little room for the intake pipe work.

http://www.ramair-filters.co.uk/shop/au ... 8cc-100mm/

Thats more like what im after to be honest. Price seems reasonable too.

I want the biggest / deepest i can fit to give rampipe clearance.

[Andy8421]

Its not a great idea to have carb mounted air filters on an Elan. As pointed out above, you want the coldest air possible (if performance matters to you) and if you use the standard layout, there is a small ram effect to be had by taking air from in front of the radiator.

A bigger concern for carb mounted airfilters is fuel soaking into the filter from the carb, creating a fire risk. 'Stand-off' at certain revs can result in fuel being ejected from the carb intakes, which can soak into the filters.

This video shows the effect at around 20 seconds in.

https://www.youtube.com/watch?v=Sx_V9t48YaM

and here at around 21 seconds in.

https://www.youtube.com/watch?v=U22yRyAykwE

[RichC]

stand-off even clearer with this one
https://youtu.be/RSSYcVTUrT8

[JonB]

That's fuel vapour? Scary.

[pauljones]

Does the fuel stand only happen on the carbs, i have fuel injection?

But either way thats a very good point.

Dont want a fire.

[MarkDa]

K&N Cone Air filter

I put a K&N cone filter on the end of standard inlet trunking.
Draws cool air and leaves a lot of room for air to get to radiator.

[prezoom]

K&N cone filters on both my S2 and Plus2. Made a gimbal style mount similar to Clivey Boys for each filter. It would appear that the videos are showing race engines with more radical cam shaft timing. Increasing the overlap increases the standoff. Not a fan of standing so close the engine when operating the dyno.

[MarkDa]

I tried to buy Cliveboy's system but not in stock at the time.
So I just shaped a piece of wood, screwed a jubilee clip to it and attached it to wheel arch.
So ?100 saved!

[Stevie-Heathie]

Fitted the Clivey Boy kit to my S3 two years ago, delighted with it.
Steve

[Spyder fan]

I have a full width radiator in my +2, but still have a K&N filter in the nose cone. You need to drill some very big holes as per the extract from the Practical Classics build of an Elan +2 Zetec.

[mbell]

The hose fits past the wide radiator on the +2. Gets squashed a little with the bonnet up but is fine.

So confused at the suggestion of drilling large holes or using carb mounted filters....

[pauljones]

So is the point to go airbox and remote filter,
I have carb mounted K&N filters at moment, ok theyre on itb jenveys. Only reason im going to change is Alan pointed out theyre a bit thin, and dont have ram pipes. So im looking at rectification of this.

If our engines were getting fuel stand off surely it would be in the air box and require draining.

[MarkDa]

I think the general view is that the stand off is not normally that prolonged in road use and the fuel evaporates into the airflow again and gets ingested.