I used to do autosolos in my ST and I had one of those and it did a good job of keeping the fluid cool
The ST has a different reservoir to the other Fiestas but if the diameters of the fittings are the same it should still work, but if they aren't you'll need a different adapter and hose and fittings. The kit isn't hugely complex it's really only the ali bracket to secure the cooler that's bespoke.
One thing to note is, if it's supplied with heater hose (like mine was), it won't last very long with the power steering /ATF fluid before it softens, you need something resistant I think I used a good grade of fuel hose
The other thing is sometimes its just the fluid spilling out of the reservoir and not actual boil over, mine continued to leak under hard driving even though the fluid wasn't hot.
The ST has a different reservoir to the other Fiestas but if the diameters of the fittings are the same it should still work, but if they aren't you'll need a different adapter and hose and fittings. The kit isn't hugely complex it's really only the ali bracket to secure the cooler that's bespoke.
One thing to note is, if it's supplied with heater hose (like mine was), it won't last very long with the power steering /ATF fluid before it softens, you need something resistant I think I used a good grade of fuel hose
The other thing is sometimes its just the fluid spilling out of the reservoir and not actual boil over, mine continued to leak under hard driving even though the fluid wasn't hot.