This thread is inspired by and made to accompany Melbzetec’s thread:
Some reflections on intakes. LR Focus
Here are several options that I have experimented with or are popular here on the forums:
1. Panel filter upgrade:
Aftermarket options are available from K&N (Part# 33-2877) or BMC (Part#FB318/01)
Pros: looks stock, small hp gains expected, last longer than factory filter
Cons: Airflow into airbox is still restricted.
2. Panel filter + intake resonator (lower airbox) removal:
There are already posts on this by:
Black LS (good instructions)
Trenchtractor (good pics)
Once the restrictive lower airbox has been removed, I would recommend routing some cold air piping into the bottom of the upper airbox, leading to higher airflow through your new panel filter.
Pros: still looks stock, more cold air into upper airbox, can still be returned to stock
Cons: stock upper airbox and intake hose may not be optimal for higher power / higher flow
3. K&N 57i Intake:
(Part #57-0595)
Installation instruction (.pdf)
Pros: high-flow, reusable filter, solid (non-ribbed) intake tube, awesome induction roar, incorporates factory crankcase breather system, reusable filter, can be imported cheaply from UK (ebay!)
Cons: open pod filter in engine bay = hot air intake. I have found it performs very poorly in the Australian summer – potential for power loss rather than gain! Exposed, oiled pod filters may be illegal in your state.
4. BMC CDA (Carbon Dynamic Airbox):
The CDA is a high-flow filter, enclosed in a cylindrical carbon fibre airbox. The carbon fibre not only looks great but also shields the filter from the heat of the engine bay. The included cold air feed pipe can be attached to the intake side of the airbox, making it a true CAI system.
The CDA comes in 2 sizes:
Type 1 (70-130) is for engines up to 1600cc
Type 2 (85-150) is for engines above 1600cc
I would strongly recommend the Fiesta ST150 / XR4 CDA kit (Part#CDASP-08), which is a modified version of the CDA85-150 unit – whilst still designed for a 2.0 Duratec engine, it is slightly smaller in length than the standard unit, giving you more room to attach a cold air feed within our cramped engine bay. You will also need a silicone hose to attach the filter up to our throttle body (BMC recommends Part# SASE13570). Here is the Fiesta unit fitted, silicone intake hose attached:
Each CDA comes with some bracket supplies to mount the airbox in the engine bay.
The CDA has no plumbing for the engine breather system, so you will need to install a little crankcase breather filter as well. I am told this may be illegal in some states so this must also be considered.
Pros: A true CAI, great induction sound, solid bolt-on HP, reusable filter, underb bonnet bling
Cons: price ($$$), universal fit, requires crankcase breather filter, custom work required to mount bracket , legality?
5. K&N Apollo
Like the BMC unit, the K&N Apollo is also a universal CAI system. However, these can be had for a lot cheaper in Australia (you can pick up a new one for <$200). Compared to the CDA, these are a smaller unit, so they fit well in our engine bay.
The Apollo units also come with plumbing options for the engine breather system (no mini-breather filters required). This, and the fact that they are fully enclosed, means that they are 100% street legal.
Attachment to our throttle body is easy. All you need is a 70mm silicone hose, with a 90 degree elbow.
Pros: street legal, compact but high flowing unit (up to 250hp N/A), cheaper than the CDA, reusable filter, true CAI
Cons: will have to let you know if I come across any!
(I have picked up a cheap Apollo and I am going to fit it soon and try it out. My CDA is not going to waste – and probably going to a good home – my mate’s Golf GTI)