Single valve springs

[sled_dog]

What is the advantage of a double valve spring vs just a single spring? I'm looking at these LT4 springs for my 383. I have yet to determine if they will fit in my spring pockets but I will do that yet tonight. My camshaft is a factory LT4 roller cam(which these springs match, and they can go higher lift if I wanted). For about $50 I can get a set of valve springs that look about perfect for my application.

 

[Mad-Dog]

more spring pressure just equates to a higher rpm limit w/o valve float,
most flat tappet cams work fine with about 285-300 psi open pressure.

roller cams require more pressure to keep the wheel in contact with the cam lobe, 350 psi and up is the norm here.

on the same note more spring pressure unless required is just wasted energy and useless wear and tear on the valve train as more HP is required to turn the reciprocating assy.

use the springs that are designed for your cam and nothing more.....

 

[R72K5]

AFAIK they shut quicker tighter than singles

good for tall lobed cam and high RPM runner, and i mean HIGH,

good luck

 

[sled_dog]

thinking with the 383, even with the LT1/TPI setup I won't spin more than 5500 so LT4 springs should be plenty.

 

[JIM88K5]

I'm gonna run the LT4 springs caps and retainers on my vortec heads...

 

[jarheadk5]

Double valve springs are designed to prevent a total loss of spring tension when the spring reaches it's resonant frequency. It has nothing to do with higher seat pressure.
The inner spring is wound slightly tighter differently, of a different gauge of wire, and sometimes even a different alloy, all to prevent valve float. Valve float occurs NOT because the motor is spinning too fast, but because the single spring has reached it's resonant frequency and is no longer elastic. It's also a safety feature in case one spring breaks, although this is more important in aviation recip engines than automotive engines.