Welcome back to another exciting update on our ‘Save the ST170’ project as we fit poly bushes to our latest Ford Focus ST project car.

In collaboration with Machine Mart, we are on a journey to ‘Save the ST170’. We’ve teamed up with Ford Parts R Us and Machine Mart to raise awareness of this unsung fast Ford because many people are breaking down many Ford Focus ST170s for parts. Far from just saving one from the scrap heap, we’re making significant to the performance of our own ST170 project car as we go. If you’re eager to embark on your own car modification journey, be sure to explore Machine Mart’s range of tools and equipment that make every automotive project a breeze.

In this update, we’re taking the first steps to upgrade the handling and suspension system with a full set of polyurethane bushes from Poly Bush.

installing a new performance poly bush

Why Upgrade the Suspension Bushes?

Polyurethane bushes are a popular upgrade among performance enthusiasts due to their superior durability and enhanced handling characteristics compared to traditional rubber bushes. By replacing your stock rubber bushes with polyurethane ones, you can expect reduced flex, improved steering response, and a more direct road feel.

This upgrade is particularly beneficial for our Ford Focus ST170. The 170bhp produced by the 2.0-litre Zetec engine isn’t as much as rival hot hatches delivered, but the ST170 makes up for it with formidable handling. Adding polyurethane bushes works in harmony with the chassis design, keeping all the right bits in all the right places to ensure the tyre is always in contact with the road.

box of Polybush products

Who are Polybush?

When it came to choosing polyurethane bushes for our Focus ST170 project, there was only one name that came to mind. A name that is literally synonymous with this upgrade, Polybush.

As a leading manufacturer of high-quality polyurethane suspension bushes, Polybush specialises in providing enthusiasts with superior products designed to enhance performance and handling. With a focus on durability and precision engineering, Polybush has established itself as a trusted name in the automotive industry, offering a range of suspension components tailored to meet the demands of high-performance vehicles like the Ford Focus ST170.

man fitting front wishbone bush

Enhancing Chassis Performance with Poly Bushes

Front Suspension Bushes

We inspected the front suspension and found that someone had recently replaced one of the front wishbones. Good news, considering our RAC vehicle report indicated that our Focus ST failed an MOT on “excessive play in the ball joint” less than a year ago. The previous owner clearly replaced it before retesting the car.

However, the ball joint on the other side was far from okay. As soon as we removed the wishbone it more or less fell apart in our hands. A quick phone call to the local motor factors saw a replacement wishbone with us by lunchtime.

With both front wishbones removed, we could head over to the hydraulic press to remove the standard rubber bushes. The press made light work of the job and after a quick clean up the wishbone was ready to accept the new Polybush front bush kit. By replacing the factory rubber bushes with polyurethane ones, we significantly reduce the amount of unwanted flex in the suspension system, resulting in improved handling and a more responsive steering feel.

suspension arm with poly bush installed

Rear Suspension Bushes and Component

As we turned our attention to the rear suspension, it became apparent that corrosion had taken its toll on various components. Many of the old bushes were severely perished and needed urgent replacement. Plus, we noticed that the driver’s side rear track control arm was badly bent out of shape too!

Optimistically, we tried liberal amounts of penetrating fluid (including leaving them to soak overnight) but it was clear this Focus ST170 was going to put up a fight! It has lived most of its life in Southend, and the salty sea air has clearly attached the suspension components and their fixings. To remove the stubborn bolts corroded in place, there was only one option – fire up the grinder. This might not be a surprise to anyone who’s replaced Focus rear bushes in the past!

rear suspension components removed from the car

With the suspension components physically removed from the car – including dropping the rear subframe – we headed to the parts washer. With everything thoroughly degreased it was into the sand blaster to remove the rust, before a coat of satin black paint had everything looking like new. Those components that were too far gone, like the lower rear arms, were binned and new replacements ordered, and the bent rear control blade was repaired

using press to install a poly bush

Then it was just a case of pressing out the rubber bushes and fitting the new performance upgrades from Polybush. A simple job, just make sure everything is lined up correctly before pressing the outer cages into place. Then, simply press the polyurethane bushes into the metal cages and pop in the metal inserts. At the same time we ordered new camber bolts and new anti-roll bar drop links.

refurbished Focus ST suspension components fitted with poly bushes

Benefits of Poly Bushes for a Focus ST

By fitting a full set of polyurethane bushes, the handling and performance of our Ford Focus ST170 received a significant boost. The enhanced stiffness provided by these upgraded bushes minimizes flex, improving response and reducing suspension play. With improved consistency in wheel alignment, you can expect precise cornering and a more engaging driving experience. Gone is the woolly tired feel associated with worn-out rubber bushings. The polyurethane bushes provide a superior fitment and long life expectancy, ensuring our Ford Focus ST170 feels planted and predictable when your start to press on through the corners.

Boxes of Bilstein suspension in front of a Focus ST170

Next Steps: Springs and Dampers

We haven’t finished bolting the rear back together just yet. We’ve still got to finish off the brake upgrade upgrade by fitting the EBC rear discs and Yellowstuff pads, and we’ve just taken delivery of a shiny new Bilstein B12 sports suspension kit to install. Coupled with the Polybush kit and Toyo tyres, the Bistein suspension kit will take the handling prowess of our Focus ST170 to the next level!

Read Part 6 as we finish off the handling upgrades.

Missed an Update?

Check out previous instalments of our Save the ST170 project!