The best thing will be to get some logs.

So we can understand whats going on.

Cheers,
Emre

 

The technique matters also - if you are driving 100 and then step on the gas then you won't get as good of a time compared to driving 80 and stepping on it to build boost by the time 100 goes by. Get a Durametric cable and datalog your car and that would be the best and most cost effective way of figuring out what's going on with the car...