I was disassembling the 455 I will be putting into my Cutlass Supreme, and noticed that the factory exhaust valve springs had a kinda flat shaped spring on the inside (a secondary spring with a different pitch/helix angle from the first spring). The internal spring is not on the factory intake valve springs.

Were these there to increase seat pressure on the exhaust valves, or for some other reason?

FYI it is a '72 455 with GA heads. ~72k miles, 2 inch intakes.

 

The flat "springs" are actually dampers. This may have been due in part to the added weight of valve rotators, perhaps?

 

Performance engines that might turn some rpm's had dampers on both intake and exhaust, even without rotators. The dampers are a good idea, and you can take them off other springs as needed. They don't really add appreciable tension, just dampen harmonics where the spring is not flexing smoothly.

 

Essentially they are to keep the springs from horizontal movement, correct Joe?

 

Not exactly. Spring harmonics are sort of like a periodic vibration where the spring is not following Hook's law, meaning it is not changing length exactly in a linear fashion with load. BTW, Olds offered a thick shim to replace the rotators for performance use, PN 231004. Or you could get a conversion pkg with 16 retainers and 16 spacers, 231003.

 

I have a set of Ga heads with the same thing always wondered what they were for.