A pack of 15 cars from GTA SA with proper dirtmaps, working sirens and using their own vehshare. Fits best into IV:SA (arguably way better than the original IV:SA cars).

PUT SAVANNA.DAT INTO THE "carmods" FOLDER! (if it doesn't exist, create a folder called "carmods" in your game folder and put the .dat there)
CARS REQUIRE THIS TRAINER TO WORK PROPERLY https://gtaforums.com/topic/896795-1000-1080-zolika1351s-trainermod-menu-rewritten/
Use https://gtaforums.com/topic/955449-iv-zolikapatch/ to use the sirens and make bulletholes appear properly

Car list:
Admiral
Alpha
Banshee
Buffalo
Bullet
Cabbie
Comet
Cop Car LS
Elegant
Esperanto
Euros
Feltzer
Fortune
Glendale
Savanna

Vehicles.ide:
admiral, admiral, car, ADMIRAL, BUCCNEER, VEH@STD, NULL, 100, 999, 0.2229, 0.2229, 0, 2, 1.0 ,0, -
alpha, alpha, car, BANSHEE, BANSHEE, VEH@STD, NULL, 10, 999, 0.2967, 0.2967, 0, 5, 1.0 ,0, -
banshee, banshee, car, BANSHEE, BANSHEE, VEH@LOW, NULL, 10, 999, 0.2967, 0.2967, 0, 5, 1.0 ,0, sports
buffalo, buffalo, car, SABREGT, BANSHEE, VEH@LOW, NULL, 100, 999, 0.2240, 0.2240, 0, 5, 1.0 ,0, -
bullet, bullet, car, INFERNUS, INFERNUS, VEH@LOW, NULL, 20, 999, 0.2500, 0.2500, 0, 5, 1.0 ,0, sports
cabbie, cabbie, car, CABBY, BURRITO, VEH@STD, NULL, 30, 999, 0.2473, 0.2473, 0, 2, 1.2 ,1, ext_taxi
comet, comet, car, COMET, BANSHEE, VEH@STD, NULL, 30, 999, 0.2621, 0.2621, 0, 5, 1.0 ,0, sports
copcarla, copcarla, car, POLICE, BUCCNEER, VEH@STD, NULL, 100, 999, 0.2345, 0.2345, 0.2,2, 1.0 ,1, siren
elegant, elegant, car, SCHAFTER, MARBELLA, VEH@STD, NULL, 100, 999, 0.2440, 0.2440, 0, 1, 1.0 ,0, -
esperant, esperant, car, SCHAFTER, MARBELLA, VEH@STD, NULL, 100, 999, 0.2440, 0.2440, 0, 1, 1.0 ,0, -
euros, euros, car, SUPERGT, COMET, VEH@LOW, NULL, 50, 5, 0.2747, 0.2747, 0, 5, 1.0 ,0, sports
feltzer, feltzer, car, FELTZER, BLISTA, VEH@STD, NULL, 100, 999, 0.2660, 0.2660, 0, 5, 1.0 ,0, sports
fortune, fortune, car, FORTUNE, FORTUNE, VEH@STD, NULL, 100, 999, 0.2250, 0.2250, 0.3,2, 1.0 ,0, -
glendale, glendale, car, ESPERANT, ESPERNTO, VEH@STD, NULL, 100, 999, 0.1996, 0.1996, 0.3,1, 1.0 ,1, -
savanna, savanna, car, FELTZER, FELTZER, VEH@STD, NULL, 100, 999, 0.2660, 0.2660, 0, 5, 1.0 ,0, livery
txdp
vehshareSA, vehshare
admiral, vehshareSA
alpha, vehshareSA
banshee, vehshareSA
buffalo, vehshareSA
bullet, vehshareSA
cabbie, vehshareSA
comet, vehshareSA
copcarla, vehshareSA
elegant, vehshareSA
esperant, vehshareSA
euros, vehshareSA
feltzer, vehshareSA
fortune, vehshareSA
glendale, vehshareSA
savanna, vehshareSA

Carcols.dat:
admiral, 0,0,22, 7,7,79, 16,16,93, 34,34,32, 52,52,50, 54,54,53, 62,62,65, 70,70,63, 72,72,64, 102,102,105, 104,104,105, 116,116,122, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80,
alpha, 0,0,22, 7,7,79, 16,16,93, 34,34,32, 52,52,50, 54,54,53, 62,62,65, 70,70,63, 72,72,64, 102,102,105, 104,104,105, 116,116,122, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80,
banshee, 0,0,88, 0,1,87, 1,1,2, 1,1,90, 1,4,8, 12,1,87, 23,23,90, 28,28,89, 31,9,32, 35,0,28, 39,39,28, 46,46,28, 49,49,118, 52,4,118, 53,53,50, 62,89,65, 66,1,71, 89,1,50, 36,4,90, 77,48,118, 16,16,19, 9,9,91, 15,0,93, 128,132,94
buffalo, 0,0,22, 7,7,79, 16,16,93, 34,34,32, 52,52,50, 54,54,53, 62,62,65, 70,70,63, 72,72,64, 102,102,105, 104,104,105, 116,116,122, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80,
bullet, 34,1,28, 0,0,2, 76,0,75, 132,0,133, 120,120,133, 20,20,4, 0,0,84, 74,74,128,
cabbie, 89,89,1,
comet, 0,0,63, 1,1,12, 33,33,27 46,46,127, 6,6,8, 49,49,59, 127,127,123, 62,62,63, 22,22,64, 56,56,59,
copcarla, 0,133,1,
elegant, 0,0,22, 7,7,79, 16,16,93, 34,34,32, 52,52,50, 54,54,53, 62,62,65, 70,70,63, 72,72,64, 102,102,105, 104,104,105, 116,116,122, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80,
esperant, 19,19,19, 16,16,16, 38,38,38, 50,50,50, 57,57,57, 72,72,72, 77,77,77, 88,88,88, 94,94,94, 97,97,97, 102,102,102, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80,
euros, 0,0,50, 3,3,2, 7,7,5, 13,13,13, 34,34,30, 33,33,29, 0,0,96, 40,40,41, 57,57,55, 70,70,71, 72,72,73, 77,77,75, 88,88,50, 104,104,107, 121,121,123
feltzer, 13,13,65, 62,62,63, 0,0,63, 1,1,64, 3,3,12, 6,6,16, 7,7,15, 15,15,17, 28,28,28, 40,40,28, 49,49,50, 50,50,51, 57,57,55, 65,65,55, 74,74,63, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80,
fortune, 0,0,1, 3,3,3, 4,4,4, 10,10,10, 16,16,76, 9,9,91, 15,15,93, 19,19,93, 13,13,80, 16,16,16, 31,31,31, 31,31,33, 34,34,34, 36,36,33, 49,49,75, 52,52,52, 56,56,57, 55,55,55, 62,62,1, 64,64,1, 68,68,72, 72,72,2, 77,77,74, 80,80,50, 87,87,74, 95,95,95, 103,103,1,
glendale, 1,0,3, 0,0,3, 7,0,7, 10,0,10, 11,1,11, 16,1,16, 21,2,21, 31,31,31, 48,38,48, 55,1,55, 57,10,57, 61,16,61, 68,102,68, 78,108,79, 95,102,95,
savanna, 0,0,49, 38,38,85, 0,97,102, 3,0,12, 6,6,4, 11,4,12, 13,13,12, 16,95,90, 24,1,12, 21,21,12, 23,23,2, 31,31,27, 32,113,34, 34,12,34, 49,13,41, 52,0,59, 62,13,69, 76,4,76, 82,85,76, 87,8,76, 89,0,4, 92,95,90, 95,95,2, 106,103,2,