Calculating deck height and selecting a HG
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Calculating deck height and selecting a HG Measuring deck height on my dished piston at the very top radius where the squish is, im getting .0185 out of the hole and -.002 in the hole rocking back and forth. Adding and then dividing, i get .0165/2 for a deck height of .00825. Is my math correct? Something seems off to me. I am trying to reach a 11.5:1 compression with a 62cc head, 4.03 bore, and 4.0 stroke (408).
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Is my math correct?
A more urgent question would be however, whether those "numbers" are an accurate reflection of reality.
Standard procedure for determining deck height in an assembled motor, is to measure directly above the piston pin. Takes all the rest of that about "rocking" and whatnot completely out of the equation.
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The valve reliefs hardly ever go all the way to the edge. There's nearly always some "crown" left.
Even if there's not, you can lay a straightedge or flat something or other across it, and use a feeler gauge at the piston pin. I'd trust that AHELLUVALOT more than any "rocking".
Even if there's not, you can lay a straightedge or flat something or other across it, and use a feeler gauge at the piston pin. I'd trust that AHELLUVALOT more than any "rocking".
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Verdad Gallardo The valve reliefs hardly ever go all the way to the edge. There's nearly always some "crown" left.
Even if there's not, you can lay a straightedge or flat something or other across it, and use a feeler gauge at the piston pin. I'd trust that AHELLUVALOT more than any "rocking".
Even if there's not, you can lay a straightedge or flat something or other across it, and use a feeler gauge at the piston pin. I'd trust that AHELLUVALOT more than any "rocking".
Scott, when you rock the pistons using 2 indicators, when you write down the results, do you split the difference? For those who may not know what I'm talking about; say one indicator reads .020" rock, and the other reads .012". When added together you get .032". Divide the .032" by 2, and you get .016". Is this correct, or am I wrong? If wrong, isn't the first time!!
, and won't be the last!!
, and won't be the last!! Scott, when you rock the pistons using 2 indicators, when you write down the results, do you split the difference? For those who may not know what I'm talking about; say one indicator reads .020" rock, and the other reads .012". When added together you get .032". Divide the .032" by 2, and you get .016". Is this correct, or am I wrong? If wrong, isn't the first time!!, and won't be the last!!
, and won't be the last!! Scott, when you rock the pistons using 2 indicators, when you write down the results, do you split the difference? For those who may not know what I'm talking about; say one indicator reads .020" rock, and the other reads .012". When added together you get .032". Divide the .032" by 2, and you get .016". Is this correct, or am I wrong? If wrong, isn't the first time!!, and won't be the last!!
, and won't be the last!! Good discussion topic Lance. Depends on the rod design and material for tensile (stretch), as well as rod fastener design and material. Block material makes a difference from a thermal growth perspective also. Worth mentioning for the discussion is the crankshaft design also. A center counterweight design will hamper crank whipping, which can alter quench at high rpm.
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Drake Engineering John Drake taught me MANY "terms"
First, a Block contained the engine Valves AND Cylinders (No Head and no Head Gasket)
The Crankcase contained the Crankshaft and Rods
Thus, the Crown is where the Valve Seats are installed.
John Drake manufactured the MOST Successful Racing Engine of ALL TIME.
His terms should be observed
First, a Block contained the engine Valves AND Cylinders (No Head and no Head Gasket)
The Crankcase contained the Crankshaft and Rods
Thus, the Crown is where the Valve Seats are installed.
John Drake manufactured the MOST Successful Racing Engine of ALL TIME.
His terms should be observed
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From: Mefis
John Drake taught me MANY "terms"
First, a Block contained the engine Valves AND Cylinders (No Head and no Head Gasket)
The Crankcase contained the Crankshaft and Rods
Thus, the Crown is where the Valve Seats are installed.
John Drake manufactured the MOST Successful Racing Engine of ALL TIME.
His terms should be observed
First, a Block contained the engine Valves AND Cylinders (No Head and no Head Gasket)
The Crankcase contained the Crankshaft and Rods
Thus, the Crown is where the Valve Seats are installed.
John Drake manufactured the MOST Successful Racing Engine of ALL TIME.
His terms should be observed