98RedBird

iTrader: (77)

Zero lash on this new motor is 7.375.

Pushrod options are 7.400 or 7.425, so I can either be .025 preload or .050.

Literature says .035 +- .010, but I've seen others running .045-.050 on them, so what do you guys think? I called Johnson, waiting on a call back.

Thanks

98RedBird

iTrader: (77)

Just talked to Johnson, going with the 7.425" rods, that will give me .050" preload. He said the aluminum motors will loosen lash/load up .015" when it comes up to temp, which will drop me in at .035" which is perfect.

53te39

Thanks for this ^ I’m at .047-.050” of preload so it will work out perfect for me as well.

12silverado

I emailed Johnson and they keep telling me .035+ or - .010 but they say don't forget thermal expansion because I have an aluminum block and heads stock so which they say thermal expansion is between .012 and .015 so does that mean my preload should be somewhere between .047 and .050 or am I misunderstanding them I have the 2110 Johnson lifters. I dont know whether they mean I should set the preload at .035 or because I have an aluminum block I should set them at between .047 and .050 if anyone could help clear this up Id appreciate it.

12silverado

So Johnson told you to run between .047 to .050 Pre load for an aluminum Block

53te39

I ended up using a different set of rocker arms which made my preload .030” average. After running the engine the valve train sounds a bit noisy after it really heats up. I’m putting in some .025” longer pushrods soon so I’ll report back if it made a difference. In theory this should get me closer to their recommend preload once warmed up due to thermal expansion. We shall see.

53te39

I used the .025” longer pushrods with no difference so I’m sticking with the ones I originally installed. It runs great, I just cannot stand these loud ls valve trains.