squealingtires

iTrader: (14)

I can't say this with any certainty but it would seem that valve float begins with the intake valve side of things and then eventually progresses to the exaust but since the exaust is quite a bit less mass it probably never floats. What if a less aggressive lobe were place on the intake like a Comp XE and a Comp LSK were placed on the exaust? Any benefit in increasing the rpm limit without needing extremely high spring rates?

Marc 85Z28

iTrader: (8)

Very common on cams that are custom designed for a specific engine. In fact, some LS1 tuners are using Ford lobes now

Asmodeus

valve float is specific to an individual valve/spring/lifter/pushrod/lobe, it's not contagious. there are a lot of reasons for it, and identical combinations of the above will tend to act similarly. BUT there are springs out that can handle an LSK lobe. Also, an LSK lobe is better for an intake valve than an exhaust valve. Speaking mainly on behalf of 2 valve engines, more lift allows more flow (generally). 2 valve engines LOVE high lift. I also believe it's easier to deal with getting excess exhaust gas out by dealing with duration rather than (small variances in) lift. I think pushing air out of a cylinder is different than pulling air in.

Ragtop 99

iTrader: (7)

Not much gained with an LSK lobe on the exhaust compared with an XER. An XER is just about as fast and once the exhaust valve starts to open, most the power is gone.

squealingtires

iTrader: (14)

I didn't mean to get too specific by naming lobe types I was just trying to use an example of different options. I guess another thing I wonder about is why it isn't very common to find different valve springs taylored to valve mass and lobe type.

Asmodeus

to an extent some are.. but they're the higher dollar racing springs. brett bauer told me about a set of beehives that could accomodate LSK lobes, but they are hard to get a hold of and are very expensive.

I guess the spring came first, they cover a wide variety of applications focusing on fitting various heads instead of getting too specific with setups. Go with TI retainers, sodium filled or TI valves, and match the spring pressure to the cam lobe. Run a good set of lifters.

should be fine.