918's, or duals with titanium retainers?
 

Ive kinda been debating on which way to go with the valvetrain, the cams I am looking at running will work fine with 918's. Just kinda trying to figure out if the titanium retainers make up for the extra mass that comes with the duals? What would you pick, 918's W/O tit retainers, PRC duals, or patriot duals. Cams im considering are in the low 230's duration and ~.600 lift, all with XER or equivalent lobes.

http://www.krcperformance.com/newcontent/beehive.html

Most people will say go with duals for the safety because of the high lift. The 918's are rated to .625 though and that link is an interesting read. Why not throw the Tit. retainers in with the 918's though?

I think that 918s will work just fine.

Why risk vavle float? I say go duals.

The PRC and Patriots are the same spring.

With the 918's I can rev past 6500 rpm with no sign of flost on the dyno :)

Look at seat (installed) pressure and open pressure not just lift. Most dual springs although somewhat safer if a failure occurs, have much higher open pressure which is harder on the valve, rocker, pushrod and cam. If you don't duals then I wouldn't get them. Talk to the cam maker and folks who've been using similar cams.

I'd say stick with the 918's and TI retainers.

I'm running the Crane Dual Springs and Tit retainers and stock cam. We have had several issues (float mostly) and determined it must be the springs. Many of the vette guys experienced this issue with the same Crane 1.8 install and when they switched to the 918's.... all problems solved. Just and FYI.

No Question, Duals. And I think (IMHO) more because that cam tops out around 7000-7200 rpm at the lift limit of 918's and with a decent duration 230+...

It may run OK for a while, but at 20K miles I'd be sweating, and listening for broken springs... Doesn't seem worth the risk...

I am not that concerned with spring life. My car only sees 3-4K per year, and by the time the springs were bad I will be able to afford a stroker. Im more interested in which will rob more power, and be less prone to valve float. My car has 77K on it now, and im *somewhat* concerned about the stock lifters. The car runs perfect, doesnt burn a drop of oil. I will most likely shift between 6400 and 6700 depending on the cam, and its powerband. You guys think the 918's with titanium retainers are worth it? Or are the titanium retainers unnecessary because of the decreased mass of a single spring over a dual spring? Im kind of a believer that if your valvetrain geometry is correct, and you treat the springs properly, that a single spring will be just as reliable as a dual. I think people really look at dual springs just for peace of mind.......

I just read the article, and there is some VERY good info in there. Because of the decreased size of the retainer for a beehive spring, titanium retainers really dont save much mass at all on them.....

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918's always seem to be underated.