Tuning my 2003 Focus ST170

[CycleSi]

What are the general recommendations for:

1) Air filter or Induction kit?

2) Manifold/Exhaust system?

Thanks.....

[stevenr]

It should already have a stainless exhaust as standard and the induction kits aren't worth bothering with unless you are wiling to pay big bucks for the enclosed kits.

Is it noise you're after or performance? For more noise just pull the resonator box of your existing airbox,gives a deeper induction note without all the fuss of an induction kit.

[CycleSi]

Unfortunatly im not too fussed with the sound, its power im after! any further recommendations? cheers

[MechEng]

From what I've seen it's fairly difficult to get more power out of these cars without supercharging or turbocharging them.

Changing to a larger and less restrictive exhaust will give you slight power gains, as will an improved air intake system. Although these will only be slight gains.

Another option would be a remap, either custom or something like a handheld Bluefin device that plugs into the car's OBD port. Gains would vary depending on the map.

[Allyc85]

Throttle bodies are the best way of getting more power with a less restrictive exhaust system from the cat backwards as the manifold is already very good.

[CycleSi]

Any exhaust system in particular?

[neiljohnson]

A vernier pully with remap and a bit of time on the rollers to adjust the cam timing correctly is the cheapest way to a bit more power. After that your best bet is saving for a supercharger kit such as the jackson racing kit where 300bhp is possible.

Failing that sell up and get an Rs which is what i did

[Chris_w666]

Vernier Pulley as mentioned frees up a little power (10-20bhp), KN type panel filter allows a little more breathing and a bluefin will make the most of them but you will still have under 200bhp unless your car is a fantatsic one.

Above that the best ways to get more power are:

1. Buy a Focus RS

2. Forced induction supercharger or turbo charger, but this needs lots of other work (supercharger less) and an intercooler, then you need to invest in OMEX or similar engine management software to take it a bit further, but I think a supercharger can give 250bhp on the standard ecu.

3. Keep the cars character and go for ITB's, a bit of old school head work is possible as I believe are slightly peakier cams, with the same OMEX or similar management can give you a proper touring car sounding, quick NA car.

I weighed up these options when I had my car, I have listed them in order of cost, difficulty and effectiveness.

Option 3 was my favourite though.