'cc check' perplexed...(HELP Requested)

sCREamnClones

New member
I am doing a freshen-up 'favor' for an 'older' friend than I on a B/S Spec motor that was built by a re-nouned builder. It's an early 'Greyhound 5-bolt' and isn't compatible w/my cc stand, of which I was not planing on 'having' too use 'on-this' anyhow. But, I have too replace all the internals and changes the 'in-hole' from .012 to .006. Simple calculation, rgt? (Wrong!) In viewing a couple things and knowing where he (old friend) is going with this, I desided too 'cc' the c-chamber and find it to be at 21.6cc w/ the LAD installed and taped off at the top (bottom) as the head is inverted resting level on my tooling plate. I 'had' a single .010 metal gasket and was .012 in-the-hole. If my #'s are correct/close....a .010 gasket and .012 in-hole gives me 'abt' 2.05cc's +21.6cc = 23.65 cc! "WHAT AM I MISSING HERE? Please give me a 'sanity' check....Thx
 
Ur missing dish in the piston and area to the top ring. It all has to be assembled to check right. Unless u have check individual pieces in the past.
Leggs
 
^^Leggs has it. .010 in the hole is usually around 5cc's (depending on the dish of the piston, they vary) in the engines I have done. A thin head gasket is 1cc....
 
Humor me; what is wrong with 23.65 CC's?
Is that not enough for the class, or is it too much?
Is this a dished piston or a flat top?
At the start of your post you said; from 12 to 6 in the hole, which is it?
With a 0.010 casket and 0.012 in the hole your math is correct. I'm thinking if you have a dished piston, you would have said so.
Update; I see in your last post it is a dished piston. Does that solve the problem?
Comments compliments criticisms and questions always welcome.
 
Humor me; what is wrong with 23.65 CC's?
Is that not enough for the class, or is it too much?
Is this a dished piston or a flat top?
At the start of your post you said; from 12 to 6 in the hole, which is it?
With a 0.010 casket and 0.012 in the hole your math is correct. I'm thinking if you have a dished piston, you would have said so.
Update; I see in your last post it is a dished piston. Does that solve the problem?
Comments compliments criticisms and questions always welcome.

I took it to mean as a result of changing the internals, it is now .006 in the hole (was .012), and the rule is 26.5cc minimum (AKRA)
 
Yes...w/the 'dish' it's good-2go. My dilemma now is....do I go w/ .016 piston/hd clearance? I've done .013's in the past on 'my' motors but it's risky on 'customer' motors. I do Not want too cut the head for (2) hd gaskets!! This is where a .016 Cu gasket wud be a nice option too have! What wud YOU do? Note; history on this motor is 62-6300 rpm and more 'squeeze' is likely too 'bump' it! (Darn rules)
 
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