Measuring Piston Rings / Shells

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SilverShadow
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Post Thu Oct 10, 2013 10:08 am

Just thinking ahead”¦..

I should be at a stage of dropping of my block and crank to get some machine work done in the next couple of days (rehone, crank polish).

The plan is that I’ll build the block up once I get it back, however I do I determine what size piston rings to use alongside the shells for the crank to use?

I done some research on plasti gauge but seems quite an primitive method to use? :?

Interested to get peoples thoughts on this.

:cool:
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ross2009
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Post Thu Oct 10, 2013 7:15 pm

if its only a rehone or and a polish standard sizes woud apply you only need to go over size if the crank has been ground or the block has been bored
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SilverShadow
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Location: London

Post Fri Oct 11, 2013 10:45 am

ross2009 wrote:if its only a rehone or and a polish standard sizes woud apply you only need to go over size if the crank has been ground or the block has been bored
That's the thing, Im not certain whether they are standard Pistons or Crank.

The engine is spec'd to a M20B27.
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ross2009
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Post Fri Oct 11, 2013 10:51 am

a 2.7 is only made by the stroke of the crank the bores should still be standard never assume anything when building an engine
and I believe the crank journals are standard size too only way to check is measure them
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