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More machine than man
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851 Posts
Factory stock TBI heads use self aligning rocker arms.
Factory stock Vortec heads use self aligning rocker arms.

As far as I know GM never used roller rockers on the Gen 1, Gen 2, or Vortec motors.

Make sure you pay attention to pushrod length before you just go swapping roller rockers willy nilly! :nono:
 

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More machine than man
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851 Posts
Here is one article. Read it, then do some more research.
Setting Pushrods Length, Quick and Easy- Car Craft Magazine

Basically the path of the roller needs to stay in the center meat of the valve stem. If it stays on the edges then it will accelerate valve guide wear. If the tip rolls off the side of the stem...oops, bad news.

Here are some things that will impact the correct pushrod length from one engine to the next, or even during a rebuild...
  • core shift causing misalignment of the cam shaft bore (or align honing the cam bore)
  • base diameter of the cam shaft
  • variation in height of the lifters (brands/designs/models)
  • pre-load on the lifters
  • block deck height
  • head gasket thickness
  • cylinder head design/casting (including how well the rocker studs are aligned with the lifter bores)
  • milling the cylinder heads
  • different brands/models of rocker arms
  • valve stem height

So I hope you can see the variety of factors involved here and that you just can't blindly swap rollers. Old stamped rockers are not sensitive to pushrod length like rollers are. You must take these things into account.
 

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WFO
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5,030 Posts
the tbi heads I have now have roller tips . stamped rockers then I can use them on my new vortecs yes just check push rods how do I do this?
You can make an adjustable pushrod length checking tool, click on the image for details:



For checking the geometry, here's a short page. The general consensus of engine builders is to shoot for a narrow roller-to-valve-tip pattern, rather than a centered pattern. If you can get BOTH a narrow AND centered pattern, all the better.

Other areas of the valve train that need to be checked are here.
 
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