Techno hows it work? question
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 800
Likes: 3
From: Port Orange FL
Techno hows it work? question
OK, here is one of those things I have always wondered about. If my engine is sitting here idling at 25 PSI of oil pressure than how does it keep my lifters pumped up against a valve spring that not only has a leverage advantage on it because of the rocker arm but has over 100 PSI when it is in the fully closed position? I think I know, but I need to be sure. Inquiring mind and all that stuff.
Roy
Roy
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by Nathan Plemons
My first guess would be that the lifters also have a spring inside of them, the oil isn't doing all of the work.
Burning Brakes
Joined: Nov 2005
Posts: 848
Likes: 1
From: 1992 LT1 6 speed Cayman Islands
Simple
When the lifter moves up the bore and it is experiencing valve spring preassure, the oil feed hole is blocked off by the bore and the lifter is like a solid lifter because no oil can leak out and the oil is not compressable.
The only time the lifter feed hole is exposed to the oil preassure is when it is down the bore, off the cam lobe, and the oil preassure simply acts on the lifter internals to tale out any slack in the valvetrain when there is NO spring preassure to contend with.
It is neither the size of the internal spring or the size of the hole in the lifter
Hope this helps
Jerris
The only time the lifter feed hole is exposed to the oil preassure is when it is down the bore, off the cam lobe, and the oil preassure simply acts on the lifter internals to tale out any slack in the valvetrain when there is NO spring preassure to contend with.
It is neither the size of the internal spring or the size of the hole in the lifter
Hope this helps
Jerris
Race Director
Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
Originally Posted by Jerris
When the lifter moves up the bore and it is experiencing valve spring preassure, the oil feed hole is blocked off by the bore and the lifter is like a solid lifter because no oil can leak out and the oil is not compressable.
The only time the lifter feed hole is exposed to the oil preassure is when it is down the bore, off the cam lobe, and the oil preassure simply acts on the lifter internals to tale out any slack in the valvetrain when there is NO spring preassure to contend with.
It is neither the size of the internal spring or the size of the hole in the lifter
Hope this helps
Jerris
The only time the lifter feed hole is exposed to the oil preassure is when it is down the bore, off the cam lobe, and the oil preassure simply acts on the lifter internals to tale out any slack in the valvetrain when there is NO spring preassure to contend with.
It is neither the size of the internal spring or the size of the hole in the lifter
Hope this helps
Jerris
