I felt it was necessary for me to add this: Jonathan Palmer drove the "third" XP5 prototype at 231mph (average lap speed)at Nardo. Referring to this (while discussing how fast a F1 will go), Andrew Frankel writes "Given that, at such a velocity on a banked surface, much of your speed is lost in tyre scrub, it would certainly have gone considerably faster on the flat...especially since its early engine was, at the very least, 50bhp down on the production version." FACT is XP5 ran 231mph. Does the above quote not state the XP5 had at least 50 less hp than the production F1? Are we going to say the XP5 goes faster than the production car which in fact ended up with more hp? I would think based on what I have just quoted, the F1 production version as well as the XP5 could have gone faster than 231mph... and just because maybe no one has seen it done doesn't mean it hasn't been done, and that also doesn't mean that it isn't possible. I admit without a problem some of my information COULD be wrong (as well as my source), as just about any information can be wrong to some degree... but it is worth considering. It seems valid to me.