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Discussion Starter · #81 · (Edited)
Well I finally have the pistons straightened out and am the the process of assembling the engine. I'm measuring the pushrods and am getting 7.300 for the exhaust valves and 7.320 for the intake valves (I'll need to add preload to these lengths). I'm running LS9 CNC heads and the intakes with the lash caps are slightly lower (i.e. .005") than the exhaust valve stems. I assume the rest of the length difference is in the cam grind since with a 1.7 rocker the .005" wouldn't make much of a difference in pushrod length. I have the BTR shaft rocker system and Johnson 2210 lifters.

A couple of questions.
  1. What should the preload be set at? I'm thinking .050" since I believe that's what @Lt1z has posted in the past vs the .035 +/- .010" Johnson shows on the box. Also it seem like others have called Johnson and they've said since the aluminum expands the .050 is fine.
  2. I assume .020" variance is too much to run the same length pushrod, correct?

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