Tire Pressures across models
 

OK Even with the Stuttgart factor how does a company spec the same tires for a Cayman and 911 (2007 as an example) and set the Cayman pressures to around 30psi then pump up the 911 tires to around 40? Before owning the Cayman I thought the reason for the super high pres in the 911 was due to the mystic N spec on the Porsche tires but I guess that doesn't apply here, does it?

Yeah I guess I didn't really think anyone would reply to this.

Part of the tire pressure requirement is to deal with the loads on the tire. The 911 transfers much more load to the rear tires under acceleration requiring more pressure.

Main factor is the potential for 4 passengers vs 2. OP if this never occurs I run 37 psi in rear for more even tread wear & better ride comfort.