[supr78nova]

The installed valve springs on a new set of heads that my brother ordered have the following spring pressure specs:
seat pressure - 115 [email protected] 1.80" IH
open pressure - 315 [email protected] 1.225"
max lift - 0.575"
spring rate - 339 lb/in

The Lunati 268 Voodoo cam 0.489"/0.504" that he is using with these heads recommends using a spring that has the following specs:
seat pressure - 108 [email protected] 1.75"IH
open pressure - 339 [email protected] 1.25"
Spring rate - 462 lb/in


I have run the numbers and the supplied springs will have ~55 lbs less pressure @ 0.500 lift than the recommended Lunati springs. Is this difference in spring pressure enough to cause valve float at higher rpm?



Thanks,
Dan

 

[Paul Wright]

The spring rate is vastly different. I would say no.

 

[supr78nova]

Paul,

Can you please clarify for me as the wording of my question is different than the way you answered? You're saying that he should not use those springs because the valves will float?

Dan

 

[supr78nova]

Paul,
Disregard the previous post...after taking another glance, I realize that your answer was in response to the title of the thread. Thanks for your help, it is much appreciated.

Dan