#61  
Old 07-24-2021, 08:23 AM
Cliff R's Avatar
Cliff R Cliff R is offline
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The first thing to do when deciding where to lash your HR lifters is to determine how much plunger travel they have.

Put the lifter on the base circle, tighten the rocker arm while spinning the pushrod until it tightens up and removes all the lash. Then start counting the turns down till it bottoms out the plunger and locks up the pushrod. Most of these heads use 7/16" fine thread studs so about .050" travel per one full turn.

From the beginning I've been paying attention to these lifters and have found versions ranging from having close to .160" travel and others closer to .060". That is a BIG deal if you are trying to put them in the center of their travel, or determine pushrod length, etc.

I used to shoot for center of their travel. In other words if there was .100" travel available I'd set them at .050" down from zero lash. Since many early versions of these retrofit HR lifters were not all that well made we'd run into a few "tickers" on occasion. This simply comes from inconsistent plunger to body tolerances and leak down rates. Most were pretty decent but for sure if you had one with a fast leak down rate it would be pretty loud once the engine was fully warmed up and oil thinned out.

So I started running all of them much tighter, even if they weren't short travel versions. So basically bottoming the plungers out then backing up the locknuts a specific number of turns to keep plunger travel to a minimum.

I don't know who supplied the Comp or Lunati HR lifters but I've seen variations in both over the years. They also started showing up with stiffer springs under the plungers in later years. Morel may have been making all of them, don't know that for sure but it really doesn't matter. I've had better success tight lashing them vs just going to zero lash then a 1/2 to 1 (.025-.050" with fine thread 7/16" studs) turn tighter to locate the plungers.

If you wonder over to Butler's website they are offering several variations of the Johnson HR lifters and a short travel variety. If I were building one of these engines with a HR cam at the moment I'd be taking a pretty hard look at those instead of Morel, Comp or Lunati.......FWIW.......

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  #62  
Old 07-24-2021, 10:35 AM
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i82much i82much is offline
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how do you tell the difference between a ticking lifter noise vs noise from the valves hitting the seats? i have OF 1.0 with the newer comp hyd rollers. it makes some noise once it warms up, but with a mechanic’s stethoscope the noise seems about the same everywhere. over 30 psi at hot 1000 rpm idle and makes kind of a “snikt” sound.

basically once the forged 2618 pistons warm up enuff to stop slapping, the valvetrain starts making some kind of noise. it’s always something!

  #63  
Old 07-26-2021, 12:37 PM
joes455 joes455 is offline
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I run hippos on my old faith full cam .set lashed at 0 negative, meaning turning force on the pushrods with fingers is the adjustment.Engine may rock a little on start up depending on eng temp but will soon stabilize .I shoot for pushrod with slight turning resistance with temp at 160.

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  #64  
Old 07-26-2021, 12:43 PM
joes455 joes455 is offline
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So forget Positive lash on these hybrids and focus on pushrod turning resistance with your fingers as the adjustable medium

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