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Old 09-04-2011, 07:31 AM
  #378  
downunder
 
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Default RE: Tapered-Bore Engine Break-in - Upgraded

ORIGINAL: DarZeelon
Mr Cox,
When you reply in a thread, it is advisable to first read through the posts to fully understand what is being discussed.
In post #337 Brian mentioned, toward the end of it, an engine with an iron piston running in a steel sleeve.
This is what the sentence you quoted relates to and it is definitely not a tapered-bore engine.
Dar, I think you should take your own advice and read what I said. I mentioned that this engine was almost impossible to turn through the pinch but you focussed on the fact that it had a cast iron piston in a steel liner. Both facts are true, it's a lapped piston engine but with a pinch. Unlike the conclusion you jumped to, it definitely does have a tapered bore, in fact I measured it as a .05mm (.002") taper from BDC to TDC.

The fact that, once I got the engine to start, it behaved perfectly normally with no trace of strain proved (to my satisfaction at least) that hydrodynamic and hydrostatic pressures kept it from destroying itself.