I heard that if I get the CTR/ITR cams for my GS-R, I will have to eventually change the valve springs and retainers. Is this true. Why would I have to change the springs and retainers, I mean do I really have to. What are the positives and negatives to doing the swap. Also how much HP can I expect from the cams. So far I have DC intake, JDM header, custom exhaust, VAFC, FPR.

 

springs and retainers are needed if you plan on moving the redline from 8000 up to 8400 or 8500 - ITR and CTR cams are still making power above 8000 rpm (where stock GSR cams don't) dropping the cams in at 0 and 0 may give you a minimal amount of power - you;ll have to dial them in (my guess would be advance the intake cam a couple of degrees and retard the exhaust one degree - but you'll have to tune them on the dyno to know for sure - dialed in you could get 7-12 whp (not sure but a good guess) - try using search function - this topic has been covered a bazillion times I be dialing in my spoon cams on a relative stock GSR (CAI & mugen exhaust - hoping for at least 10 whp, but I need to get a VAFC - to adjust vtec cross-over and fuel.