if the temps are as normal without that particular front mount then here lies your problem. is your intercooler in decent nick? bent fins at the back will cause problems. or maybe its a badly designed cooler. if the fins a too dense it will act the same as bent fins while its up against the rad. although the air is forced through the cooler then rad, the rad will still act as a restriction if the cooler is already having difficulty in pushing air through the fins. its a shot in the dark but id definitely look at trying another cooler and inspecting yours for damaged fins. also compare the core/fin spacing next to another decent fmic (rad tec or grs) what make is your intercooler?