MK2 Ford Focus ST225 Tuning Guide
The MK2 Focus ST225 is one of the most iconic fast Fords of its generation. The 2.5-litre 5-cylinder Volvo-derived engine is a brilliant platform with huge power and torque gains available — even at Stage 1, the transformation is dramatic.
We've tuned hundreds of these on our in-house 4WD DynoDynamics rolling road here in Coventry.
We'll be honest — these cars are getting on a bit now, and the condition of the car you start with makes a massive difference to the results you'll get.
We see everything from well-looked-after examples to cars that have had a hard life, and the two tune very differently.
If you're planning on tuning yours, it's well worth making sure the basics are sorted first — fresh plugs, clean oil, no boost leaks, and a healthy engine. Get the foundations right and these cars reward you massively.
All power figures in this guide are based on real results from our own dyno — not manufacturer claims. For optimal results, 99 RON fuel is required.
Stock Where you're starting from
Ford rated the Focus ST at 225hp, and on our dyno that's roughly what we see from healthy standard cars.
The 2.5 five-pot has a distinctive character and a lot of headroom for tuning, which is what made these cars so popular in the first place.
Stage 1 — Remap Only A completely different car
A Stage 1 remap completely transforms the Focus ST225. With no hardware changes at all, a custom remap on our rolling road will take you from 225hp to 260–275hp and 360–380ft/lb of torque. That's a huge jump — especially on the torque side — and it makes the car feel like a completely different animal.
At this stage, we advise fitting an induction kit to get the best from the remap, though they're not essential for Stage 1 power levels.
Stage 2 — Intercooler + Exhaust + Induction Where the ST225 really comes alive
Stage 2 is where the Focus ST225 really comes alive. With an upgraded intercooler, a 3" exhaust system, an induction kit, and a clutch upgrade, these cars make serious power — typically 300–320hp with torque capped at around 420ft/lb.
At this spec, we're also at the limit of the stock fuel injectors.
- Upgraded intercooler
- Induction kit
- 3" exhaust system
- Clutch upgrade (MK2 RS clutch)
- Custom Stage 2 remap
For a full 3" turbo-back system you'll need all three pieces: downpipe, mid pipe, and cat-back.
A Note on Block Modding Worth researching
Block modding is a big subject when it comes to the 2.5 five-cylinder engine. In simple terms, it involves fitting shims that fill the gap between the cylinder liners inside the engine block.
Some owners swear by it, and some run for years without it with no problems. It's worth researching and making your own decision on this one — if you'd like to discuss it, drop us a message.
Supporting Modifications Chassis & handling
The Focus ST225 is a big, heavy front-wheel-drive car with a lot of torque going through the front wheels. As you add more power, investing in the chassis makes a real difference to how the car handles and puts that power down.
Coilovers — A set of BC Racing BR Series coilovers will completely transform the handling. Adjustable ride height and damping lets you dial in the setup for fast road, track days, or a balance of both. The reduction in body roll and improvement in turn-in over the stock suspension is dramatic.
Control Arms — The standard front control arms and bushes are a known weak point on the MK2 Focus platform. A set of SuperPro front control arms with uprated bushes will tighten up the front end significantly and improve steering feel and response.
Complete the Look Styling upgrades
Once the performance is sorted, it's worth finishing the car off with some styling upgrades to match.
We stock a full range of splitters, side skirts, spoiler extensions, and diffusers for the MK2 Focus ST225 — all designed to give the car a more aggressive look without going over the top.
Browse all MK2 Focus ST225 Styling Parts →Quick Reference Power by stage
| Stage | Mods Required | Power | Torque |
|---|---|---|---|
| Stock | None | ~225hp | — |
| Stage 1 | Remap (+ induction kit & clutch advised) | 260–275hp | 360–380ft/lb |
| Stage 2 | Intercooler + 3" exhaust + induction + clutch + remap | 300–320hp | capped at 420ft/lb |
All figures based on real dyno results at Wayside Performance, Coventry. Individual results may vary depending on the condition of the car, fuel quality, and ambient conditions. 99 RON fuel required.
Ready to Get Started?
Whether you're after a simple Stage 1 remap or planning a full Stage 2 build, we'd love to help. All of our tuning is completely custom and carried out on our in-house 4WD rolling road in Coventry — no generic off-the-shelf maps. Every car gets a before and after dyno printout.
Got questions? Drop us a message on the live chat or email us at Support@Wayside-Performance.co.uk
