[R] boxcox transformation

[Torsten Mathies]

I've got a vector of data (hours to drive from a to b) y. 
 
After a qqplot I know, that they don't fit the normal probability. 
 
I would like to transform these data with the boxcox transformation
(MASS), that they fit the model.
 
When I try
 
ybx<-boxcox(y~1,0) 
qqnorm(ybx)
 
the plot is different from
 
library (TeachingDemos)
ybct<-bct(y,0) //
qqnorm(ybct)
 
How can I transform y to fit with the normal probability model?
 
 
Yours
Torsten