Ford Sierra Tuning

"Sierra problem mate?"

When you look at the mighty RS Cosworth and RS 500 you start to appreciate the potoential of the Sierra Chassis. Ignore the 1.6 as this is seriously underpowered. The XR4 and XR4x4 models give a good amount of power and handling.

The breakers yards provide a treasure trove of parts for the Sierra with many drivers going for engine swaps from the high performance models.

The Sierra Cosworth Box mated to an MTX80 gearbox profvides the power for many kit cars. If you have a non performance varient then improving the handling should be your first priority in your Sierra tuning project. We suggest that you fit uprated suspension and lower the car by 35-40mm. Larger drops require arch work - especially on models already equipped with sports suspension.

Turning our attention to the Sierras engine we need to get a bit more power out of the top end.

Smaller engines do not provide much of a return in terms of power so start with a bigger engine. Engine swaps are a good option if you have a small engine size.

Ford Sierra Tuning modifications.

A fast road cam will be one of the best power mod you can do mechanically to your engine. Don't forget to uprate the fuelling when you are increasing the power - it makes the car more thirsty. Improve your cars response to the throttle with a Fuel pressure boost valve. Uprating the injectors is another beneficial modification and will deliver sufficient fuel. When increasing your fuelling you will also need to get a bigger fuel pump to supply it.

Ford Sierra Intake and Exhaust.

The next area for modification is the intake and exhaust. For small Sierra engine sizes go with a washable panel air filter. On larger engines and turbo vehicles an induction kit will help increase power. Sports exhausts balance the flow of air throughout the engine. But if your exhaust is too larger (over 2.5 inches bore) you will lose back pressure on most engines.

When you start tuning your Sierra you will find that the standard clutch starts to complain so get an uprated clutch. NASP engines do not achieve big power gains if you remap them but with turbo engines this is another story. A remapped turbo remapped turbo will give phenomenal power gain. Adding forced induction will see big power gains but this is usually too expensive to be cost effective. It is easier to bolt on a supercharger than it is to get a turbo working. With a turbo the boost curve is related exponentially to the engine speed making it hard to map. Superchargers however will give a boost which is proportional to engine speed so is easier to map. Adding forced induction will usually require a lower compression ratio or water injection.

Ford Sierra Wheel modifications.

Because alloy wheels are lighter they improve performance and they help to cool the brake disks. Large Sierra alloy wheels can decrease performance. If you get big alloy wheels you will be changing your final drive ratio. Aim to keep the overall rolling diameter of the wheel the same as supplied from the factory. In all cases we do not recommend going above 18 inches.

The Cosworth alloy wheels will always look nice and if you are lucky enough to track down a set from a breakers yard we would recommend that you snap them up quickly.

Please join us in our forum to discuss the Sierra options in more detail with our Sierra owners. It would also be worth reading our Ford tuning articles to get a full grasp of the pros and cons of each type of modification.