I'm not sure how big your helmet is, but I'm sure as hell mine only covers my head. I still have my arms, legs, and torso to worry about... You know that area that has all bar one of your vital organs?
If you stack a car at 150KM/H, and a 2KG object comes loose (The weight of most objects) it is like being hit by a brick wall... Even a mobile phone coming loose in a 100KM/H crash is enough to kill someone if it hits you in certain locations.
There is a reason that the tracks have a "NO LOOSE OBJECTS" policy.
Secondly, if it's just not tuned on timing, who gives a fark, so long as it doesn't ping at anything above 3500RPM... Even half the race cars out there don't data log shit!