I don't know how accurate the speedo is but, on my last trip to L.A. from S.F. I averaged about 85mph. On the way back I hit about 85-105mph. At one point I had the speedo at the 110 mark. This was on Highway 5. All flat and straight. I wasn't pushing it as hard as it wanted to either. What I do know is that I was mighty close to the redline. I had the tach at about 4000-4100 rpm for about an hour and a half before my senses kicked in to what I was doing. From then on, I averaged about 90 mph. FYI, my car is a bone stock 84 300D turbo. I had just changed the oil and done a coolent service on it as a precausion. I just got a boost control from Dawes Devices and am gonna bring the boost back to about 13.5 psi. By the way, it is very stable at those speeds. I had a lot of confidence in the car. Even in cross winds.