VL will win if your stock,
approx 105 kw to 114 for the VL and the Vl is lighter im pretty sure.
Especially if both are auto.
When my XF was stock i got done by heaps of VL's consistantly. My XF is a manual too.
I raced a mate in his auto VL and lost. Then i had head, cam and intake done and i beat him by heaps very consistantly, All VL's except turbo dont stand a chance now.
When my cam was changed my old one was very worn tho, yours might be different.
But still with the sluggish auto box you will struggle.