Powerflex lower engine mounts are also a very worthwhile mod for the XR4.
Ford (in their wisdom) used the same lower mounts on the more powerful ST/XR4 as all the other WQ Fiesta's models (DOH!) ... Result = lower mounts wear out very quickly and crack leading to extensive engine movement in the engine bay, this of course then leads to exhaust joints, mounts and the flexi pipe breaking etc.
Pumaspeed is but one company that sell them,
http://www.pumaspeed.co.uk/showdetai...?productID=103
I actually got mine from
http://www.larkspeed.com/ ... they was a bit cheaper at the time.