I'm no drag race expert, but I can use my head and know physics pretty good.
If you spin and a beginning of the track, with out moving forward then the ET will be higher and the MPH should be the same.
However if you spin as you move forward or spin when changine gears, you are effectively reducing the time you have to get to top speed. There for it is possible to have lots of HP, have poor traction and have a low MPH.
Just my $0.02
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1995 Mustang GT