I would expect the 0-400 time of the XR6 to be around the same as the XT, in manual form. I am pretty sure that the time of 15.28 would have been done in a manual. There is no way that an Auto XR6 would be 6 tenths slower with a better diff ratio.
In regards to actual times of the XR6 manual I haven't seen any articles that feature the N/A XR6 in a manual form. I guess this is because the 'journos' think the base XR6 is good enough to take on the Supercharged S and this only comes in auto. Therefore they take the auto XR6.
BAII XR6T, Lightning Strike, M6, Sports Steering Wheel, 18" Wheels.
"Anyone can drive in a Straight line"