[lincpimp]

If the tires are not taped, you are not getting much ballooning, and I have run those tires un taped and under about 40 they do not balloon much. So I just do not think you are doing more than 40 cause of the lack of ballooning. Just my experience though. Get a radar gun. I have the bushness one and it is great. We used it to get accurate reading on all of my rcs. I compared it with my cop buddy's mounted radar and it was only a few % off.