Well I'm sure you guys have heard this one before. It's the old "I'd like to put in some cams do I need to upgrade springs and retainers" question. Just got done reading a 263 post thread over on evom that had Buschur vs. Revolver debating whether or not the stock spring retainers would hit the valve seals if HKS (272 or 264) cams were installed. Bushur was convinced there was no issue. Revolver insisted there was (and that everyone needed to buy their springs and retainers kit to remedy the problem). Numerous pictures and calculations claimed the additional 0.8mm of lift from the HKS cams over the stock cams would be enough to bring the retainers and seals into contact. The conclusion (and overall concesus) of that thread appeared to be "they do hit". Of course there are multiple (reliable) sources that have said it's nothing to be concerned about. Bushur stated they had installed hundreds of sets of cams in evos without upgrading and without any problems at all. I also asked AMS who said stock springs and retainers would be fine. Now there's no doubt in my mind that leaving stock springs and retainers in would be "fine", but just because it's "fine" doesn't mean it's "right".
So what do you guys think? Is it an issue? Did those of you running cams upgrade springs and retainers or not?
