Will this clear?

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Jun 15, 2023 | 10:13 AM

65LSXNOVA

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Launching!

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From: New Athens IL

Will this clear?

First off I want to say I will measure before installing this cam. Build is as follows. 6.2 SBE with flycut pistons .060. TFS 235 heads milled .060
felpro HG .041 thickness. Pistons measured .007 above deck at TDC. Current cam is a Torquer V2, going to swap in a 239/247 .626/.625 114.
what's are your thoughts? Need deeper flycuts?

Jun 15, 2023 | 11:15 AM

Kawboom

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Most flycuts on pistons are much deeper than necessary but you really, really need to check during mockup. Be sure to use an adjustable pushrod and preload your hydraulic lifter all the way to the end.

Jun 15, 2023 | 07:49 PM

jayyyw

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What do you mean by preload your hydraulic lifter all the way to the end?

Jun 15, 2023 | 07:55 PM

Che70velle

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Quote:

Originally Posted by jayyyw

What do you mean by preload your hydraulic lifter all the way to the end?

I wondered the same, and I think he’s referring to having the lifter artificially all the way up with shims or washers internally…

Jun 15, 2023 | 08:35 PM

jayyyw

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Quote:

Originally Posted by Che70velle

I wondered the same, and I think he’s referring to having the lifter artificially all the way up with shims or washers internally…

That's what I was thinking too. I have some old johnsons that I added a second spring to make them solid, for purposes like this.

Jun 15, 2023 | 10:43 PM

low2001gmc

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From: ELSA, South TEXAS (956) 802-7700

Quote:

Originally Posted by 65LSXNOVA

The 114 LSA helps with Piston to Valve Clearance, but best to check. What is the LSA Advance?

Rob D

Jun 23, 2023 | 06:47 PM

grinder11

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Quote:

Originally Posted by low2001gmc

The 114 LSA helps with Piston to Valve Clearance, but best to check. What is the LSA Advance?

Rob D

Yes, the 114°LSA helps, I agree. Just a guess, but an educated one; I think..625" lift on a 114 will be fine, especially with pistons already cut .060".

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Jun 24, 2023 | 07:29 AM

Double06

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From: Potomac, MD

You can also do the valve drop method at TDC but you need the cam lift at TDC (on opposite cylinder when both valves are open during scavaging phase) which some manufacturers do publish (Comp Cam does and other have the numbers avaiable with different LSA points 106/110). Say your cam is .100 lift at TDC (opposite) you have a 1.7x rocker arm so the lift at TDC is .170. You take your head at TDC drop the valve see how far it drops say .350 so that is .180 clearance but I like to reduce that by .050 to account the valves closest point is a few degrees after TDC. The mock up is the best method but this method is helpful when picking a cam and all you have is the engine with no cam and trying to figure out what to buy that will fit.