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Old 02-18-2026, 01:44 PM
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chiphead chiphead is offline
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Quote:
Originally Posted by HWYSTR455 View Post
Again, you never add/subtract lash when calculating pushrod length, because the lifter will pump up. Even for solid lifters you don't add/subtract. Solid lash is to account for thermal expansion/contraction/deflection. (possibly other factors too)

If you question it, contact a high-end builder and ask, someone who uses half-lift method.


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They never show the lifter in the BBC used as an example in that video. If it was a solid roller, then you don't have to worry about preload or lash to get the pushrod length right. But in a hyd lifter engine, the amount of desired preload will increase the pushrod length. If you wanted to run a deep preload like Cliff recommends, you'd have to add the amount of preload required to put the hyc lifter cup near the bottom of its travel.

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