Air filters, induction, etc

[Mick K.]

Hi,

I'm coming up to my 45K service, and I had planned to replace my factory air filter with something like a K&N panel - but I'm pretty sure I have heard that doing this with the standard airbox in the Focus is not that good an idea, and can create problems with oil from the filter fouling up some sensors, etc (or maybe this was with my old Golf???)

I have also read that getting a full cold air induction (CAI) system, doesn't really do that much for the car either - especially for the cost - and the positioning of the filter to get a good airflow is difficult and there are problems with heat soak.

What I have read is a good idea is to get the snorkel off an ST170 and put them on the Zetec, and either get an ST170 airbox or cut the original airbox to fit the slightly wider ST170 snorkel.

Anyone who looks at FFOC (Ford Focus Owners Club UK) web forums will see a full step by step on how to do this in the Filters/Induction Kits forum. Here is a link - non-members may not be able to see it:

http://www.ffoc.co.uk/forum/viewtopic.php?t=49410

Anyone got a panel filter (K&N or otherwise) and either recommend it or not?

What are the chances of Aus Ford dealers stocking ST170 bits like this?

Obviously the auto air deflector fits into this improved air flow equation too.

These will be my first mods - other than tinting - so am looking forward to it :

MK

[murcod]

I've got a K&N pod on my ST24 and haven't had any problems. Some people put too much oil on them and supposedly this can get into the MAF sensor and cause it to fail.

[melbzetec]

I've put a BMC filter in my Zetec, no problems.

I looked at the whole ST170 airbox swap thing, but you are looking at enormous cost.......something like $600-$700!!! Ford have obviously priced it to make it prohibitive to do.(that is snokel and airbox combined)

Its easier in the UK because with the greater population of cars, there is more chance of getting it from a wrecker.

You can do just the snorkel, but it doesn't fit the standard Zetec airbox (round hole, square peg sort of stuff), so you have to muck around cutting the airbox and using silastic and bits of plastic or aluminium.

Haven't done it, and obviously doesn't fit as well as a standard Focus part, but on a cost basis, you are (IMO) better off looking at something like a BMC carbon airbox.

Overall though, none of these approaches really give big kw gains

[Timmeh]

I have a K+N, no regrets, even got the car dynoed before and after, showed an increase in 3kw and 5Nm even though the temp rose 2 degrees between runs.

Not that it matters, but the car runs better with it, than with the std paper filter from Ford.

Tim

[b2tf]

A K&N is on the way for me. I expect nothing from it in the way of power gains (although if they come i will of course gladly accept them!), my main reason is because i do a lot of country driving, and i like to be able to clean it out, re-oil it and put it back in again. Basically just stopping going through heaps of filters.

[zetec]

K&N panel all the way, more oomph, I re-oiled it a bit too much first time round, but a few surges and hesitations later and it all got burnt out the back pipe like the rest of the stuff anyway, runs like a charm.

[Suth]

yep, K+N is the go. Mine is due for a re-oil soon though.

[brother]

Originally Posted by Suth

yep, K+N is the go. Mine is due for a re-oil soon though.

slightly off topic, but how often are you meant to clean/re-oil them. Mines probably done about 12,000km

[b2tf]

Somewhere around 25,000kms or so i think, more regularly if youre doing a lot of driving in dusty areas. I usually just check it every time im in poking around the engine bay.