Cjisntgay presents to you:
McLaren MP4-12C GT3
replaces Infernus in the game
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all the model credit goes to Kunos Simulazioni(Assetto Corsa)
convert to GTAIV by cjisntgay
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noteworthy features:
HD exterior & interior model
multi-livery is avaliable
additional template (by Kunos Simulazioni) for making custom livery (.PSD)
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Known problems:
none ,if anyone get any problem with this mod, leave your feedback at:gta4-mods.com
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How to install:
First BACKUP all the stuff you want to edit or replace!
Then using SparkIV or OpenIV to open the archive "Grand Theft Auto IV\pc\models\cdimages\vehicles.img" and replace any cars you like(example:infernus)
Lastly browse Grand Theft Auto IV/common/data and open the following files with notepad, replace the following lines for the car you replace.

HANDLING.DAT:
INFERNUS 1250.0 4.5 85 0.0 0.0 -0.53 0.5 6 0.5 1.1 325.0 0.68 0.66 0.7 35.0 1.70 2.15 15.5 0.12 0.48 3.0 2.5 2.5 0.10 -0.14 0.0 0.5 0.55 1.0 0.55 0.5 0.0 1600000 60440010 00000001 1
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VEHICLES.IDE:
infernus,	infernus,	car,		INFERNUS,	INFERNUS,	VEH@LOW, VEH@LOW_INFERNUS, 1, 0, 0.255, 0.255, 0, 5, 1.0 ,0, sports
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CARCOLS.DAT:(at car3 section)
infernus,	 132,0,0,
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Then now enjoy with the car!