bbc question

Old 05-06-2009, 08:25 AM
  #1  
taps
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Default bbc question

what is minimum piston to head clearance on steel rod bbc?
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Old 05-06-2009, 09:07 AM
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TS1955
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I typically run "zero" deck clearance and a Felpro #1027 head gasket which has a compressed thickness of .039. So my piston to head clearance is .039. Hope this helps. I'm sure others do it differently.

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Old 05-06-2009, 10:46 AM
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curtisreed
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Watch your piston rock depending on how "big" your BBC is. RPM will also play into it some. Just some things to think about in the equation.

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Old 05-06-2009, 02:28 PM
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ARUSSELL
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We recommend a min of .040 between the piston and the head.
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Old 06-17-2009, 11:00 PM
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russ67chevelle
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my motor builder said once upon a time they set up thier pistons .005 thousandths in the hole
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Old 06-18-2009, 04:52 AM
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curtisreed
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Originally Posted by russ67chevelle
my motor builder said once upon a time they set up thier pistons .005 thousandths in the hole
russ,
That doesn't tell you what the p to h clearance is. You could still have .060".

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Old 06-18-2009, 06:01 AM
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dparker
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Plus the gasket....
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Old 06-18-2009, 02:24 PM
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desoto30
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I think russ67 meant .005" = a "std" style gasket say 0.039" compressed & you'll generally be ok. X2 As doorracer says depending how "big" & rpm. I don't understand the last post.
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Old 06-18-2009, 07:32 PM
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I dont see what would be hard to understand. .005 in the hole plus the gasket .039 would give you .044 clearance, between the flat part of the piston and the head. Which is where most pistons hit. Especially if because of the piston rocking in the cylinder.
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Old 06-18-2009, 07:35 PM
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Mine hit on the dome right by the intake valve...Motor was already together so I had to grind on a brand new set of heads.
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