Ok so I just got a set of 315/35/20 with 13 miles on them. Came off a brand new BMW X5 suv with the "m" package. They are continental conti sport contact 5p ssr ( self sustaining runflats).they are 526.99 Ea new but I got a really good deal on them. They are 110 heavy load and have a w speed rating,, and they are supposed to be the direct competitor to the michellin pilot super sports. My question is what psi should I run in them. Max psi is 50 but I'm putting down 630/629 at the rear. I know they're not going to dead hook snd are still going to spin but hopefully not as bad as the 275 nexens that came on the truck. These tires are massive compared to them and should be a good bit softer. I've read a few reviews about them and saw nothing but great reviews and esp in wet conditions. Anyways just looking for recommendations on psi and any input on the tires if anyone's had experience with them.