Take you 300 Wheel HP and add (low number to be safe)15% = 345HP to the engine of a contour.
Now your 340 for the M5 add 15% (just to make it equal) you get 391hp. so you need about an extra 50 Flywheel Hp to match a M5.(less because our cars are lighter say 40hp)
But in actuality 18% is more accurate for the BMW's so 340 + 18%= 401hp so you need about 60 Hp extra (to be safe) to walk over a M5. Any l;ess than 50hp is cutting it close.
i hope i didn;t confuse people.
Roz
