Relieving the pressure on valve springs

[jdincau]

Hi all,
     What is the consensus on relieving the pressure on valve springs when
the engine is sitting idle? We have not been racing every meet this year and
I was wondering. This is for the engine in the street roadster, the engine
in the modified is never together long enough to worry about it.
Jim in Palmdale

[Dynoroom]

Jim, IMO it depends.....     how much spring load (pressure open), how much lift, are you having valve train issues? etc.
A .600 lift cam with 350lb. over the nose no. A .850 with 850lb is a different story.
If it's a moderately built engine just rotate it from time to time. That's how I do it. If it's going to sit 8+ months you could back off the rockers if it makes you feel good.
But what do I know........

See you at the salt?

[jdincau]

Jim, IMO it depends.....     how much spring load (pressure open), how much lift, are you having valve train issues? etc.
A .600 lift cam with 350lb. over the nose no. A .850 with 850lb is a different story.
If it's a moderately built engine just rotate it from time to time. That's how I do it. If it's going to sit 8+ months you could back off the rockers if it makes you feel good.
But what do I know........

See you at the salt?

It's kinda in between .695" at the valve and 620 Lbs. over the nose.
No issues yet.
Yes Ken and I will have the modified there, north end of the SDRC pits if we can or next to Fred Blanchard if we can't.

[jimmy six]

Jim, I always back off my GMC's rockers over the winter. When the engine is ready, like it is right now, I turn it over every other day with a 18" ratchet with socket on the crank.