The H&R 50750 is a set of Sport Springs for the 2008–2010 Pontiac G8, listed by the manufacturer for that model range. Its approximate drop is 1.4 inches at the front and 1.3 inches at the rear. Lowering the car shifts its center of gravity down, which reduces body roll in corners and brake dive, so the car feels more planted without the cost of coilovers. You keep your factory struts or shocks, which makes this a practical upgrade for a daily-driven G8 that also sees occasional track or spirited road use. Search terms this part matches include G8 sport springs, 2008-2010 G8 lowering springs, G8 GT lowering springs, G8 GXP front and rear drop, and H&R G8 50750 sport springs.
Fitment is the first thing to confirm before ordering, since H&R's application data covers the 2008–2010 G8 range and listings vary on trim detail. Owners on user forums who have fitted H&R sport springs to other cars consistently recommend a professional wheel alignment soon after the swap, and that advice is worth following on a G8 as well. Front struts require a proper spring compressor, and the work is best done with the car on stands, a jack, and a torque wrench. Because lowering changes camber and toe, budget for an alignment as part of the job.
The manufacturer lists the 50750 for the 2008, 2009, and 2010 Pontiac G8. Confirm your model year and trim against the manufacturer's fitment data before ordering.
The manufacturer gives approximate figures of 1.4 inches at the front and 1.3 inches at the rear. Some listings show different ranges, so confirm the final drop with the manufacturer if you need a specific ride height.
User forums covering H&R sport springs on other vehicles recommend an alignment soon after installation to protect tire wear and handling. Plan for an alignment on your G8 as well.
This is a moderate-to-advanced DIY job. Front springs sit inside the strut assemblies, so you will need a strut spring compressor and a way to safely hold the strut while you remove the top mount. Owners on user forums working with H&R sport springs on other platforms report that the rear is simpler, but that dropping the shock mounts and compressing the springs takes time, so expect most of a day for a full set. Watch the spring isolator placement against the spring seat, and do not reuse any worn hardware. Once the springs are in, book an alignment as soon as you can, since camber and toe will change.
