The H&R 29299-1 is a sport lowering spring set for the QQ6-generation Jaguar XK Cabrio, XK Coupe, and XKR, and it replaces the factory coils at each corner. Owners on user forums who ran coilovers alongside H&R springs describe the coilover setup as firmer but more controlled than the springs alone, The ride is firmer but more controlled when compared to the H&R springs alone. That contrast helps buyers decide whether a spring-only upgrade matches their priorities, and it is a lower-cost route to a lower, more planted stance on a grand tourer.
Plan the install around the front struts, since the coil sits inside that assembly. Owners on user forums warn that compressing coils with budget tools is risky, and one described a compressor retainer pin breaking under load, One of its retainer pins broke while the spring was under pressure. Near disaster when that side slipped free. Another suggests letting a shop handle the compression work, for the cost of the tool, you can have a shop mechanic do it for you. Search terms like "XKR QQ6 sport springs 2007-2014," "H&R 29299-1 lowering springs," and "XK convertible coil spring install" match this kit.
This is a coil spring swap at all four corners, so it requires a jack, jack stands, a spring compressor, and a torque wrench. Owners on user forums who worked on the earlier XK8 platform recommend a quality compressor or professional help, and a post-install alignment is wise. Confirm the exact tool list and torque specs against the manufacturer's installation instructions for your model year.
