We were speculating on the aero aspect of the Xk8's and decided to google the info. There are figures for both Coupes and the Convertibles. The Coupes show figures as low and .32 up to .36. The Convertibles show slightly above the Coupes, .33 to .36.. These figures seems reasonably favorable for era. Thinking back to the boxy Monte Carlos (GM), LTD" (Ford), and K Car (Chrysler), 0ur cars are SLICK!

 

I have always assumed, along with the gearing, that this is the reason for the 155 MPM top end, LIMITED! I think that I recall reading on here that someone got the speed limiter over ridden and they got up to about 162.