Southbend clutches for the '05-10 Cobalt, '04-07 Redline, and '08+ HHR SS with the F35 transmission. 

Just because a clutch pedal is harder to push, does not mean that the pressure plate is heavier. It just means that the pressure plate was built a different way. The ZZP Stage 4 clutch has a similar to stock pedal feel but has held over 550 ft lbs at the wheels in Matt's ‘08 LNF Cobalt SS without slipping.

Stock pressure plate is 1200#s.

Stage 2 (up to 300 ft lbs)- Discontinued - Used a stock modified pressure plate to increase clamp load. The discs metal backed Kevlar® linings provide a smooth engagement and have the torque capacity to handle high horse power, high revving engines . These clutch kits maintain a stock feel at the pedal and have unmatched durability. Front and back of metal backed TZ Kelvar® lining. The steel backing gives this lining the ability to spin up to 15,000 rpm. Will not support the extra torque of turbo applications.

Stage 3 (up to 350 ft lbs)- New Sachs upgraded pressure plate, increased clamp load above what the stock pressure plate and is rated at about 1600#s. It comes with a full face ceramic sprung disc.

Stage 4 (up to 400 ft lbs)- New Sachs upgraded pressure plate, increased clamp load above what the stock pressure plate and is rated at about 2100#s. It comes with a full face ceramic sprung disc.

Stage 4 plus (up to 475 ft lbs)- 2200-2300# intended for 400+whp setups.

'04-07 Cobalt/Redline S/C (LSJ) we recommend a Stage 3, or a Stage 4 or 4 plus for large builds(usually turbo).

'08+ Cobalt SS T/C (LNF) we recommend a Stage 4 or 4 plus (LNF's make much more low end torque than the LSJ).