Try with this magic posted in gp4italia forum
[GP4 magic file]
16 ; fw
9 ; rw
20 ; 1st
28 ; 2nd
36 ; 3rd
43 ; 4th
50 ; 5th
57 ; 6th
18 ; fw
13 ; rw
20 ; 1st
28 ; 2nd
36 ; 3rd
42 ; 4th
49 ; 5th
55 ; 6th
16 ; fw
9 ; rw
20 ; 1st
28 ; 2nd
36 ; 3rd
43 ; 4th
50 ; 5th
57 ; 6th
5773 ; unk (dw)
18 ; fw
13 ; rw
20 ; 1st
28 ; 2nd
36 ; 3rd
42 ; 4th
49 ; 5th
55 ; 6th
5713 ; unk (dw)
57 ; hard tyre
56 ; soft tyre
100 ; >= 50 tyretype 1 else 0
16384 ; unused
16384 ; unused
16384 ; unused
16384 ; unused
19500 ; track grip
16384 ; unused
16384 ; unused
24 ; related to next value below
1018 ; ride height
19000 ; air resistance?
8152 ; fuel???
384 ; subtracted from diff between field_e2 of 2 cars and then compared to speed of first car
15216 ; tyre wear
64768 ; added to car.field_108. related to cc grip factor
512 ; grip???
485 ; ?? cc power factor ace
486 ; ?? cc grip factor ace
485 ; ?? cc power factor pro
450 ; ?? cc grip factor pro
475 ; ?? cc power factor semi-pro
440 ; ?? cc grip factor semi-pro
462 ; ?? cc power factor amateur
424 ; ?? cc grip factor amateur
448 ; ?? cc power factor rookie
407 ; ?? cc grip factor rookie
1 ; ?? cc random perf range min
1 ; ?? cc random perf range max
1 ; some chance. same chance multiplied with race perc.
64 ; segment count, range 1 to 256
1 ; sectors to pit in 1
0 ; sectors to pit in 2
20480 ; pre pit speed limit
17015 ; fuel consumption 1
17015 ; fuel consumption 2
3389 ; cc shuffler???
12 ; a segment nr before which flag 0x80 in car.flags_ce is not cleared
13780 ; timing factor? (dw)
0 ; timing factor finetune? (dw)
11053 ; helps decide if a tyre set needs changing? (dw)
18000 ; same as above (dw)
0 ; rain chance
6 ; segment nr (start of some range)
6 ; segment nr (end of some range)
0 ; another perf factor
13000 ; unk (dw)
233 ; unk (dw)
10000 ; unk (dw)
2048 ; unk (dw)
190 ; unk (dw)
120 ; new (dw)
80 ; new (dw)
80 ; new (dw)
0 ; new (dw)
1814 ; new (dw)
896 ; new (dw)
0 ; new (dw)
0 ; new (dw)
0 ; new (dw)
16384 ; unk (dw) (always 16384?)
16384 ; unk (dw) (always 16384?)
16384 ; unk (dw) (always 16384?)
16384 ; unk (dw) (always 16384?)
16384 ; unk (dw) (always 16384?)
16384 ; unk (dw) (always 16384?)
0 ; pitstop group 1 %
0 ; stop 1
0 ; pit window 1
0 ;
0 ;
0 ;
0 ;
0 ;
100 ; pitstop group 2 %
22 ; stop 1
10 ; pit window 1
35 ; stop 2
10 ; pit window 2
0 ;
0 ;
0 ;
0 ;
0 ; pitstop group 3 %
0 ; stop 1
0 ; pit window 1
0 ; stop 2
0 ; pit window 2
0 ; stop 3
0 ; pit window 3
0 ; failure chance : suspension
0 ; failure chance : loosewheel
0 ; failure chance : puncture
0 ; failure chance : engine
0 ; failure chance : transmission
744 ; failure chance : oilleak/waterleak
0 ; failure chance : throttle/brake
0 ; failure chance : electrics
16368 ; unused
16256 ; unused
16128 ; unused
15872 ; unused
30208 ; bump factor
16 ; bump shift
[bumptable]
0,0
29,2
45,0
160,1
197,0
231,2
261,0
315,2
360,1
385,3
404,0
491,3
495,0
512,2
543,0
575,2
635,0
649,3
668,0
745,2
783,1
818,2
840,3
856,0