Cams need replacing?

Wonder if anyone can help me? If my Primera GT sounds like a diesel when it starts up does this mean the cams need replacing? I thought it just needed an oil change - but last time the oil was changed it helped matters but not many weeks later the noise started to get worse again. I understand that this is expensive! My question really is, if I have to replace them is it only mildly more expensive to replace them with performance cams? Cheers!

oooooh, get some JWT S3 Roller cams from www.jimwolftechnology.com i think youll be more than happy with the quiet idling and performance to boot! They arent that much, $540 USD plus shipping.