Page 54 - Fast Car (March 2020)

5 FITTING There are only two real tips here: look at the
Sometimes, to battle heat in a tight engine bay, instructions first, and remember that hose clips
an intake will be developed to relocate the filter don’t need to be tighter than a… well, you know
away for the heat source or to an area (say, what I mean. Just nip them up. You don’t need to
behind a bumper vent) where it’s likely to pick go mad and risk cracking any plastic housings. If
up more could air. Most often though, you’ll find the hoses included are tight to slip on, use a tiny
your kit will have been developed to sit exactly smear of washing up liquid to help.
where the old airbox came out.
In the vast majority of cases, an induction kit
will use the original AFM housing for ease of
fitment, too. The new filter will fit on the airbox
end and, the other will fit to either the original ever hold them by the plug end and be careful
intake pipe, or a new one from the kit. The only not to touch the sensor element if it’s exposed.
exception is where some flagship kits have their Apart from that (and making sure you look
own CNC machined housing for you AFM. for any extra breather pipes connected to the
The trick here is to be extremely careful when airbox) the principle is pretty simple. Remove
unplugging and removing the sensor from the the whole airbox, bolt on your new kit, and that’s
housing. These are extremely delicate, so only about it.

6 PERFORMANCE AIRBOXES AND ENCLOSED RAM FILTERS
Although many induction kits will come with One of the best modern solutions is the
heat shielding when needed, the last, and some performance airbox kit. K&N spent years
say best, solution is an airbox kit. developing their vehicle-specific 57S kits,
Basically speaking, some cars produce and and the idea is that they use the bottom part
retain more heat under the bonnet than others. of the standard airbox, but with a new lid that
This is perhaps most prevalent when it comes incorporates a high flow, high surface area cone
to hot hatches. They tend to have big engines, filter. These are engineered for a whole lot more
or baking hot turbochargers crammed into a airflow, but with the protection of the airbox.
tiny area and not too much room to relocate a Oh, and they’re bloody easy to fit. If you need
filter out of the bay. Often the airbox is located any more endorsement, this is the one fitted on
right next to the hottest components out of my own Corsa VXR. Practice what you preach
necessity – there’s simply nowhere else to put and all that.
it. So, unless there’s enough other tuning going
on to make mega airflow a priority over heat
protection, this is where it wouldn’t be ideal to
run an open cone filter. All you’ll do is suck in all
the hot air.
Over the years, manufacturers have
developed filters to give plenty of extra flow,
but to protect from heat by enclosing the filter.
A ram filter setup for example will fit just like
an open cone, but have ducting designed to be
mounted somewhere in the bumper to pick
up the air from outside the bay. These can be
direct-fit or universal items.

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