Model formula:
hp ~ cyl + disp + mpg + drat + wt + qsec + vs + am + gear + carb

Fitted party:
[1] root
|   [2] cyl < 7
|   |   [3] mpg >= 21.45
|   |   |   [4] disp < 87.05: 62.250 (n = 4, err = 140.8)
|   |   |   [5] disp >= 87.05: 91.833 (n = 6, err = 1376.8)
|   |   [6] mpg < 21.45
|   |   |   [7] qsec >= 15.98: 112.857 (n = 7, err = 306.9)
|   |   |   [8] qsec < 15.98: 175.000 (n = 1, err = 0.0)
|   [9] cyl >= 7
|   |   [10] drat < 3.18
|   |   |   [11] mpg >= 12.8: 170.000 (n = 7, err = 1150.0)
|   |   |   [12] mpg < 12.8: 210.000 (n = 2, err = 50.0)
|   |   [13] drat >= 3.18
|   |   |   [14] carb < 6: 246.000 (n = 4, err = 582.0)
|   |   |   [15] carb >= 6: 335.000 (n = 1, err = 0.0)

Number of inner nodes:    7
Number of terminal nodes: 8