how bad is it slipping? is it only when your really putting your foot into it? You should be ok to drive it as long as its not slipping under normal driving. stay out of boost and no aggressive driving and it will last, you just cant have any fun.
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, they have sme package deals. i have been running there flywheel and exedy singe stage kit for almost 80k and it still pulls hard as hell and doesn't slip. If you have major mods then you need to spend some money on a nice heavy duty clutch. you will need to buy a flywheel or have it resurfaced. a clutch job on a evo is not for the faint of heart and not for someone who has never done one, dealer charges anywhere from 8-13 hours of labor to do it. Do you have a lift at your house? (its not needed but will make life so much easier) do you have a couple friends that can help you? do you have a good air compressor and tools? Do you have another car you can drive while your putting the clutch in?