Like Viper X, I’ve driven my car for quite a few miles but at speeds approaching 165 MPH in numerous Silver State events. 165 MPH is the Silver State’s imposed “Tech Speed” limit based on my safety equipment but also happens to be my personal comfort limit. I think what you may be experiencing is the combination of factors that give a Viper its very visceral feel: exhaust noise, stiff suspension, stiff tires, very direct steering feedback – and as other have pointed out – so much torque that at these speeds the throttle remains very responsive with accompanying noise and acceleration changes: lots of sensory inputs. With the exception of one event when I was running too much negative camber (the car was darting all over the road above 120 ), it has always been very stable and has much more speed potential than I care to explore.
I add 4-5 psi for high speed driving events and suggest you check out TireRack’s “Air Pressure/Load Adjustment for High Speed Driving” web page at:
Tire Tech Information - Air Pressure/Load Adjustment for High Speed Driving