Chevy High Performance
Click here to find out more!

Valve train geometery and hyd lifters.

  
Chevy High Performance
Item Posts    Sort Order

Valve train geometery and hyd lifters.

 
rebuildman rebuildman
New User | Posts: 2 | Joined: 02/07
Posted: 09/16/13
07:55 AM

I read the sticky on checking for correct pushrod length, but I have a question. Using a solid lifter to do the checking, is it set to the length of the hydraulic lifter when it is fully 'pumped up', inner plunger against the snap ring. Or do you set it at the length it would be with the required preload on the lifter, 3/4 to 1 turn down on the rocker nut? I have made a solid blank lifter out of brass and used the preloaded size to do my checking, would this be incorrect?
When the engine is running are the inner pistons on the lifters up against the snap ring or at the preloaded position? Or something else?
Are all hyd. lifters created equal, perform the same way?  

76Skylark 76Skylark
Guru | Posts: 853 | Joined: 12/11
Posted: 09/16/13
11:19 AM

Unless you are doing something Really Radicle,heavy on the decking or milled heads  a stock length push rod is good to go.Tall deck blocks, really big cams, taller spring/valve stems is where you run into problems, as Hyd. lifters are somewhat forgiving. If your brass took into account the cuo for the rod tip it should work.and a 1.6 rocker will work without problems. A Rhodes lifter has a bleed off hole so a big cam can make some Vacuum at low RPM but act normal after RPM goes Up  

rebuildman rebuildman
New User | Posts: 2 | Joined: 02/07
Posted: 09/17/13
05:25 PM

So the reason I ask is I recently purchased a car with a 1958 348 engine. I found that there was a severly bent push rod on one valve and several rocker arms with major wear patterns on the valve stem end. One rocker was so bad it had fallen off the edge of the valve stem and almost cut the rocker arm stud in half. So I am trying to make sure the valve train geomerty is correct. Apparently this is a problem with this engine.  

76Skylark 76Skylark
Guru | Posts: 853 | Joined: 12/11
Posted: 09/18/13
10:16 AM

As Big a Fan of the W motor as I am I can't answer your Question. Around Here the Man is Lamar Waldon. They even Have Aluminum Blocks/Heads if you got Cash. Really though He is Who to Call.Atlanta Ga. (maybe Decater Ga.)