The carbon fabric itself will survive many hundreds of degrees and is not the limiting factor for almost all applications. The limiting factor will be the heat distortion temperature of the resin system you plan to laminate this fabric with.
An engine rocker/cam cover may easily be exposed to hot oils at around 120°C as well as heat from the exhaust which would be dependent on the engine configuration and level of tune. As such we would recommend considering using a higher temperature resin system such as our Very High Temperature Epoxy Laminating Resin which, with an appropriate post-cure, can be used up to 180°C.
An alternative option would be to consider making the part with an out of autoclave pre-preg carbon fibre where typically the resin systems can achieve a HDT up to 120°C.